DEAN Ashton’s ankle surgery was a success, according to West Ham United manager Gianfranco Zola.

The England striker underwent arthroscopic surgery on his left ankle to remove scar tissue on Wednesday, but the Italian admitted he still has no idea how long the 24-year-old will be out of action for.

Ashton, who missed the entire 2006/07 season after breaking the same ankle while training with the national team in August 2006, was hurt on Zola’s first day in charge at Chadwell Heath two-and-a-half weeks ago.

“Dean had an operation which fortunately went well,” the Irons’ boss confirmed at his Friday press conference.

“We still don't know how long he'll be out for but hopefully he'll be back soon.

“It's too early to say when he's back. We'll have to wait and see.

“He needed a clean-up because a few parts were going around in the ankle and had to be removed.”

Ashton will be on crutches for at least six weeks following the procedure, which involved putting a small camera into an incision in his injured joint.

And Zola is not expecting the £7.25million player to return to first-team duty until January 2009 at the earliest.

Meanwhile, defenders James Collins and James Tomkins are still not ready for Premier League football.

Wales international Collins – who played 70 minutes in the 4-3 reserve team win over West Bromwich Albion on Tuesday – and England Under-19 star Tomkins have both been out of action with knee ligament problems.

“Collins and Tomkins won't be available because they're not fit enough but everyone else is available,” Zola confirmed.

Another player who will not be considered for Sunday’s match is former Spain striker Diego Tristan, who has been training with the Hammers this week after being released by Serie A club Livorno at the end of last season.

“Diego is here working for us on a trial,” the manager confirmed.

“We haven't made a decision yet. Technically he's very good.

“He needs to work a little bit on his fitness but he knows how to play football.”