Nottinghamshire admit they face a fight to keep Alex Hales after two other clubs made approaches for the player.

While Hales may appear an unlikely target in some ways - as an England opener in all three formats, his availability for county cricket is limited - such is his ability in white ball cricket, in particular, that he could prove a huge asset in a relaunched T20 competition which might well, sooner or later, become the centrepiece of the domestic season.

That has quickened the interest of Essex, for one, a county with sharpened ambition under the cricket chairmanship of Ronnie Irani.

Hales is out of contract at Nottinghamshire at the end of the season and, as things stand, the club have not opened contract talks with the player.

"We want Alex to stay," Mick Newell, Nottinghamshire's director of cricket, told ESPNcricinfo. "But we haven't wanted to clog his mind with contract talk when he is trying to earn an England contract. We have had a couple of approaches for him from other clubs but, as an England player, people may wonder how much they are going to see of him.

"His game has matured. He has come to terms with practice. His general approach has improved through being around guys like Alastair Cook and Joe Root and he has learned a lot about how to prepare.

"It was a brave decision not to play at the start of the year. I admire that. He gave others the chance to perform and Sam Robson and Adam Lyth did that. But apart from England, he has played pretty much non-stop for three years with the Big Bash and Notts and he felt he needed a break. It was a ballsy decision."

With Hales largely unavailable to Nottinghamshire anyway, the club have made moves to find a replacement batsman. As well as confirming they had made an approach for Warwickshire's Varun Chopra. Essex are interested here, too. Newell also hinted they had interest in the Durham pair of Scott Borthwick and Mark Stoneman.

"We have put in a 28-day approach for Chopra," Newell said. "And we have put in 28-day approaches for the top order batsmen who are available. We've made contact with those counties."

Meanwhile, Newell rated Warwickshire as "the best team" in Division One of the Championship and said they had "every chance" of lifting the trophy at the end of the season. Accepting that his side were "on the wrong end of the game" he admitted he had some relief when rain saw the final day abandoned at around lunch time.

"Warwickshire have so much experience and they don't have the same injuries as Yorkshire," he said. "Rikki Clarke is an outstanding bowler these days and Boyd Rankin is bowling very quickly. And with Trott and Bell available all the time... I think Warwickshire might be the best team."

Newell also said he hoped that Stuart Broad, who is keen to return to the England white ball teams, would be released by England to play in Nottinghamshire's T20 match against Durham on Friday - and suggested that Jake Ball should also feature.

Hales is already confirmed to play in the Championship match that starts at Trent Bridge on Sunday and has expressed his desire to play in both. Imran Tahir, who lands on Friday morning - having flown from the Caribbean - is also expected to play on Friday night.

Ball did not reappear on the third day of Nottinghamshire's Championship game at Edgbaston having carried a heavy workload on the second day. Although he reported a sore elbow, Newell said he would have been fine to bowl had a couple of wickets been required for victory.

"He's been in the 12 for the last three Tests," Newell, who is also an England selector, said. "There are question marks over Jimmy Anderson so Ball has to have a fine chance of being in the 12 and possibly making his debut.

"He surpassed what we even expected from him here. He bowled with exceptional pace; as quick as I've seen from him. He's up to mid to high 80s, I think.

"I was a bit concerned before this game as he hadn't bowled much over the previous few weeks, but he's done very well. He has a lovely action, he has worked hard in the gym and he feels ever more confident in the England environment. I'm sure he'll play Test cricket."

With a Test debut at Lord's highly likely - England look resigned to being without Anderson or Ben Stokes - Ball may well be rested from Nottinghamshire's next Championship game with an eye to keeping him fresh for his Test debut. They will have Broad, Tahir and Harry Gurney back for that game.

"If Jake is going to get a Test call, we want him going into the best shape possible," Newell said. "We will look at Jake's workload with the prospect of giving him a rest. He has bowled an awful lot."