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Alviro Petersen maintained his stunning early-season form for Somerset as LV= County Champions Warwickshire were made to work hard for their wickets at Taunton.
Fresh from striking 167 and 91 on debut for his new county at the Kia Oval last week, Petersen appeared in tremendous touch once more as he contributed 136 to a home total of 358 for six.
The South African built on the efforts of Marcus Trescothick and Nick Compton, who each made fifties after Somerset won the toss, and found a long-term ally in England limited-overs wicketkeeper Jos Buttler, who was similarly fluent en route to 90 not out.
With the exception of the hard-working Rikki Clarke, Warwickshire’s seam attack - so integral to their recent success - struggled to pose problems for much of the day on a true surface, particularly when Petersen and Buttler joined forces for an authoritative partnership of 193.
The number three timed the ball sweetly throughout his 188-ball stay and was able to score freely around the wicket, while Buttler, solid in defence yet quick to punish anything loose, showed there is much more to his game than the innovative strokeplay he has become famed for in the shorter formats.
However, there was late reward for Dougie Brown’s men as Petersen and Peter Trego fell shortly before stumps.
Warwickshire were unfortunate not to make an early breakthrough when Trescothick, on six, appeared to edge Chris Woakes behind, only to be given not-out by umpire Martin Saggers.
The former England left-hander soon settled into his stride alongside a confident Compton, although Trescothick did endure a moment of discomfort when being struck on the neck by a Clarke short ball.
After bringing up his half-century with a glorious driven four off the expensive Oliver Hannon-Dalby, Trescothick fell lbw for 51 when propping forward to Jeetan Patel’s first delivery, ending a stand of 103.
Compton soon followed - for one more than his opening partner - to another leg-before verdict, although he could feel hard done by as an inside-edge off Clarke went unnoticed.
When James Hildreth - caught at square midwicket when mis-timing a pull off Woakes - and Craig Kieswetter, who edged Chris Wright to second slip, departed cheaply after lunch, Somerset were in danger of undoing their hard work.
Yet Petersen, in ominous form from the outset, and Buttler quickly wrested the initiative back from Warwickshire with a fine demonstration of batsmanship.
Both drove well and were given the opportunity to cash in on a series of loose deliveries as the visiting attack threatened to lose their way.
Petersen reached his century from 128 balls early in the evening session, but - to their credit - Warwickshire responded well and claimed a brace of late breakthroughs with the second new ball.
Finding his best rhythm of the day, Wright induced an edge to second slip from Petersen, and there was further pressure applied to Buttler, who was struck on the glove, and new batsman Trego before bad light forced a brief stoppage.
When play resumed, Trego was caught behind for three when looking to pull Woakes, giving Warwickshire a further boost heading into the second day.
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