Alastair Cook warmed up for the start of next week's Ashes series with a century on the opening morning of England's match against Warwickshire.

The Essex left-hander hit an unbeaten 100 off 161 balls to help England reach 185 for three halfway through the afternoon session on the first day of a three-day encounter at Edgbaston designed to give them match practice before next Wednesday's Ashes opener in Cardiff.

While Cook picked up where he left off in his last England performance, he hit 160 in the emphatic Second Test victory over West Indies at Chester-le-Street in May, Kevin Pietersen's lack of fluency in first class cricket this year continues.

After replacing captain Andew Strauss, who was dismissed by seamer Naqaash Tahir for 31, Pietersen survived just eight balls before being caught behind off Rikki Clarke's bowling for just one.

Injury, playing in the IPL and World Twenty20, and England's dominance of the West Indies in spring have given the talismanic batsman little chance to practise at the longest form of the game and he will have hoped for more time at the crease.

The other England wicket to fall was that of Ravi Bopara, who hit 43 runs off the 71 balls he faced.