Kevin Pietersen hit an unbeaten 177 on his return from injury 16 days before the start of the Ashes.
The batsman blasted his way to a near run-a-ball ton for Surrey in their LV= County Championship match against Yorkshire at Headingley.
Pietersen's selection in next month's Trent Bridge opener had been placed under some uncertainty after he took longer than expected to recover from a knee injury which caused him to fly home from England's tour of New Zealand in February.
Pietersen was in fine fettle 16 days before the Ashes begins
The 32-year-old reached his century from just 106 balls - and went on to hit 17 fours and seven sixes.
Provided he suffers no setbacks, Pietersen is due to make his England return in Thursday's second Twenty20 international against New Zealand at The Oval.
Kevin Pietersen hits unbeaten century
Yorkshire v Surrey - LV County Championship Division One(01 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(02 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his half century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(03 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(04 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(05 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(06 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey leaves the field after his side declare during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(07 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches 150 runs during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(08 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches 150 runs during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(09 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey leaves the field after his side declare during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(10 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(11 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(12 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen (L) of Surrey celebrates after he reaches his century with team-mate Steven Davies during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(13 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen (R) of Surrey celebrates after he reaches his century with team-mate Steven Davies during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(14 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(15 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(16 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(17 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(18 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(19 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(20 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey celebrates after he reaches his half century during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(21 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(22 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(23 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(24 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(25 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(26 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey bats during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(27 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey makes his way back to the pavilion after some batting practice during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(28 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey signs autographs for fans on his way back to the pavilion after some batting practice during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(29 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey makes his way back to the pavilion after some batting practice during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(30 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey makes his way back to the pavilion after some batting practice during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)
Yorkshire v Surrey - LV County Championship Division One(31 of31)
LEEDS, ENGLAND - JUNE 23: Kevin Pietersen of Surrey makes his way back to the pavilion after some batting practice during day three of the LV County Championship Division One match between Yorkshire and Surrey at Headingley on June 23, 2013 in Leeds, England. (Photo by Clint Hughes/Getty Images) (credit:Getty Images)