Yorkshire's depleted bowling attack turned out to be much stronger than expected at Headingley yesterday and bowled out Warwickshire for 233 on a rain-hit da.

But Yorkshire, who replied with 29 for one, were left to ponder over whether pitch liaison officer A C Smith would report the pitch for taking too much spin on the first day.

The original strip was too damp to use after the recent bad weather and following communication with Lord's the game started on the pitch used for one-day matches on Sunday and Monday.

Warwickshire lost half of their wickets to slow bowlers but most of them were to ambitious shots, rather than excessive turn.

With Yorkshire having seven fast bowlers absent for various reasons, it was essential that Chris Silverwood made his mark after Warwickshire had won the toss and he did so with his second ball, which feathered captain Michael Powell's bat on its way to Richard Blakey.

But then Nick Knight, averaging over 100 in the Championship, batted with great fluency, well supported by Mark Wagh, and soon Yorkshire were having to bring on their two gentle medium-pacers Anthony McGrath and Gary Fellows.

Knight cruised to his 50 off 63 balls and the stand had moved on to 96 when McGrath struck with consecutive balls and narrowly avoided claiming what would have been one of the more unexpected hat-tricks in Yorkshire's history.

Wagh was caught at slip off the last ball of an over and with the first delivery of McGrath's next Ian Bell went back and was trapped lbw. Dominic Ostler was then rapped on the pads but the loud appeal went unanswered and there would have been a further wicket later in the over if Blakey had not put down Ostler.

Rain caused the day's only stoppage soon after lunch but there was enough time before it came for Knight to aim a big drive at Richard Dawson and slice a fast slip catch at head height to Darren Lehmann.

On the resumption, Ostler lost his off-stump to Silverwood and Dougie Brown's lavish sweep at Dawson ended with him being lbw.

Jamie Troughton cut Andy Gray to Chris Elstub at backward point, Silverwood picked up his third wicket with the dismissal of Keith Piper and Lehmann's spin cleaned up the last two in the order.

Yorkshire then lost a wicket in the eighth ball of their innings - Vic Craven offered no stroke at a straight one from Mohammad Sheikh.