Theo Walcott says there is nothing that can keep Mesut Ozil down after the Arsenal playmaker returned to form with a bang against West Ham.

Arsenal went into Wednesday's clash at Emirates Stadium having won just one of their last six Premier League games, but second-half goals from Ozil, Walcott and Olivier Giroud got them back on track.

The Germany international also registered an assist, making it only the second top-flight game in which he has scored and set up a team-mate this season – the other being the reverse fixture against West Ham, which the Gunners won 5-1 in December.

Ozil's performance came after he had felt unfairly criticised following the Champions League last-16 exit to Bayern Munich, but Walcott was in no doubt he would bounce back.

"Goals always breed confidence in players, but Mesut is a fantastic player," said Walcott.

"He has played for Real Madrid, is a World Cup winner and has been through a lot of ups and downs – so there is nothing he can't come back from.

"He has put his head down, worked hard in training and the rewards showed against West Ham."

The win ensured Arsenal moved up to fifth and within four points of the top four following Manchester City's loss at Chelsea and Liverpool's draw with Bournemouth. 

Arsene Wenger's men hold at least one game in hand on all of the teams above them and Walcott is hopeful they are back in the Champions League hunt.

"I'm sure the manager will have a plan in motion and who knows – we have done it in the past," said the 28-year-old. "We have been in this situation before, although probably not as bad.

"It's the Premier League and [the unpredictability is] why it's the best league in the world. Who knows who is going to win each game?

"No one expected Liverpool to draw against Bournemouth, but that is the way it is and that is why we love and enjoy playing in this league. It is the best to be involved in."