|County Championship Division One, Taunton (day one, close):|
|Surrey 317 v Somerset 42-2|
|Somerset 3pts, Surrey 3pts|
Kevin Pietersen hit his first century since being dropped from the England Test squad as Surrey made 317 on day one against Somerset at Taunton.
Pietersen scored 163 of Surrey's total before the hosts stuttered in reply.
He hit 20 fours and three sixes in his 168-ball innings as Surrey aimed for a crucial victory in their bid to avoid relegation from Division One.
Somerset reached 42-2 in reply with Arul Suppiah and Marcus Trescothick falling inside the first six overs.
Pietersen was dropped from the national side earlier this month after allegations he texted tactical advice to opposition players during England's second Test against South Africa.
Surrey had been reduced to 73-3 following the dismissals of Zafar Ansari, Rory Burns and Arun Harinath before Pietersen and Zander de Bruyn added 91 runs for the fourth wicket.
Somerset's Sajid Mahmood, on loan from Lancashire, took four wickets, including the dismissals of Gareth Batty and Stuart Meaker in successive deliveries.
Pietersen, who made an unbeaten 234 against Middlesex in his last championship appearance, was the last Surrey wicket to fall, when he picked out Jos Buttler off Mahmood's bowling.
Surrey's Jon Lewis had Suppiah caught behind by Gary Wilson before Stuart Meaker took Trescothick's wicket as the hosts made a poor start to their reply.
Somerset, fourth in the table and with an outside chance of winning the championship title, will resume on Wednesday 275 runs behind with Chris Jones and James Hildreth both on 15 not out.
VIEWS FROM THE COMMENTARY BOX
BBC London 94.9's Mark Church:
"Kevin Pietersen was simply magnificent on the opening day at Taunton. His 163 guided Surrey to their first innings total of 317 and Pietersen scored his runs when it really mattered for Surrey.
"He batted as only he can and dominated proceedings, mixing the sublime with the outrageous, and he looks in prime form, as he has done all summer.
"For Somerset, Sajid Mahmood was the pick of the bowlers with his four wickets.
"But they then found themselves struggling with the bat as Jon Lewis and Stuart Meaker got rid of Arul Suppiah and Marcus Trescothick.
"It was a good day for Surrey and it really was a masterclass from Pietersen."