West Ham 1 Manchester City 0

The Swiss international caught his studs in the turf after 38 minutes and appeared to twist his knee. He was given oxygen and there was a lengthy stoppage before he was carried off.

He was due to have an MRI scan to assess the extent of the injury but it looks likely he will miss the rest of the season.

The injury took the gloss off the win over big-spending City, who included ex-Hammer Craig Bellamy in their ranks.

The Welshman, who moved to Eastlands for £14million in January, was booed from the moment he took to the Upton Park pitch until he was substituted after 66 minutes.

Bellamy made little impression on the game, much to the Hammers' fans delight, and appeared to suffer a knock that led to his withdrawal.

Star man for the Irons was Bellamy's Welsh international team-mate Collison, who had a couple of decent chances before finally beating Shay Given with a clever lob in the 71st minute.

The goal was a direct result of some excellent approach play by Savio, on as a substitute for the luckless Behrami, who penetrated the City defence before unleashing a fierce drive from the left that Given could only parry into Collison's path.

It was a fitting way for the Welshman to celebrate St David's Day but he was more concerned that his goal had given the Hammers their first win in six games, and helped banish memories of last Wednesday's non-performance at Middlesbrough in the FA Cup.

He said:"It was very important. The boys felt we let ourselves down on Wednesday night, not just ourselves but we had a lot of travelling fans so it was disappointing for them as well.

"We felt we had to put things right today and I think we put out a good performance and obviously took the three points."

City had their own chances to score and nearly stole a point in injury time when Elano's free-kick was glanced to safety by Lucas Neill when it looked destined to find the top corner of Rob Green's net.

This was a much better display from the Irons and they shackled City's multi-million pound outfit pretty effectively, although Robinho was guilty of wasting two great opportunities.

Radoslav Kovac made his Premier League debut for the Irons and began to look more comfortable in midfield after an uncertain opening period.

Zola admitted his side were desperate for the win, and their hunger was probably the difference between the teams.

He said: "I think it was a close game but maybe we deserved it a bit more than them, it was a crucial game for us and a very important win for us.

"I am looking up the table now. I'm a positive person and I always look up.

"I only focus on the good things that can happen to me. We are seventh and we want to stay in this position now.

The Hammers will travel to Wigan on Wednesday night in a better frame of mind as they look to push on in their quest to qualify for Europe next season, although Behrami's absence will undoubtedly be felt.

West Ham: Green, Neill, Ilunga, Upson, Tomkins, Behrami (Savio 43), Kovac (Spector 83), Parker, Collison, Cole, Di Michele (Lopez 87). Unused subs: Lastuvka, Sears, Payne, Stanislas.

Booked: Parker, Kovac

Goal: Collison, 71

Manchester City: Given, Richards (Caicedo 15), Bridge, Zabaleta, Dunne, Ireland, Kompany, Onuoha, De Jong (Bojinov 88), Bellamy (Elano 66), Robinho. Unused subs: Hart, Vassell, Garrido, Berti.

Booked: Kompany, Ireland.

Attendance: 34,562

Referee: MIke Dean