India have taken an early decision to rule out Zaheer Khan at Trent Bridge, but England will wait until Friday morning to decide whether Chris Tremlett is fit enough to take his place. He has been struggling with a hamstring problem since the fourth day at Lord's and while Andrew Strauss remained optimistic on Tremlett's chances the signs weren't promising as he struggled during training.

Tremlett bowled in two stints but the second lasted only a handful of deliveries which he bowled off one pace before leaving the field again. He had earlier run in harder - although at far from top pace - against Alastair Cook in the full nets before getting further treatment from the physio both on the outfield and in the dressing room.

Tremlett was outstanding at Lord's, where match figures of 4 for 124 didn't reflect his constant threat as he troubled all the India batsmen, but with this game starting just four days later it puts a huge strain on the fast bowlers while there is also the longer term view of two further Test matches to follow.

Strauss spoke about Tremlett's chances moments before the very brief second spell in the middle and the captain's bullishness may yet be misplaced. "We are very confident he will be fine but like all of these things, because there is such a short turnaround, we have to wait until this afternoon or tomorrow morning to make a decision," Strauss said. "We'll only pick him if we are 100% sure he'll get through the game."

England are also blessed with plenty of capable reserves and Tim Bresnan will slot into the line-up should Tremlett be ruled out, although Steven Finn has also been called up as cover. Bresnan came close to replacing Stuart Broad at Lord's but, due to his own injuries at the start of this season, still hasn't played a Test since his key role in helping secure the Ashes in Melbourne and Sydney.

Tremlett's extra bounce has clearly unsettled the India batsmen - even the best were hopping around against him at Lord's - so his absence would be a blow, but Bresnan's fuller length and swing will be well suited to a ground that often gives the pace bowlers some assistance. As a by-product he would also give England an even stronger lower order alongside Broad and Graeme Swann.

"Tim Bresnan certainly hasn't let anyone down when he has played for us," Strauss said. "He was outstanding in Australia and he's getting better and better. In many ways he's unfortunate not to be playing at the moment and if he does come in he'll do a great job."

One of the main reasons Tremlett's international career stalled following his promising start against India in 2007 was a string of injuries which meant he was often sidelined for Hampshire. However, his move to Surrey last year coincided with an injury-free time which propelled him back into the England squad for the Ashes and since his comeback at Perth he has played seven consecutive Tests.

Andrew McGlashan is an assistant editor at ESPNcricinfo