ARSENAL must suffer for 48 hours and use the anger of their 1-0 home defeat by West Ham United to rekindle their Premier League title challenge, manager Mikel Arteta said on Saturday.

It was meant to be a weekend when Arsenal would put pressure on leaders Liverpool by beating West Ham and closing the gap to five points ahead of Liverpool's game at champions Manchester City on Sunday.

Instead, a toothless Arsenal lost at home in the league for the first time in 10 months and could find themselves 11 points adrift come Sunday night.

"Very disappointed, obviously very angry as well. I think you have to congratulate West Ham for the victory and the game that they played," Arteta told reporters.

"But as well I think a lot from our side that we never got right. Even though we had 20 shots, I never felt that we were at the standard and the level that we needed.

"We have to be (angry), I hope we are very much because we didn't hit the levels today and I am very much responsible for that so I am very, very angry."

With forwards Kai Havertz, Gabriel Jesus, Gabriel Martinelli and Bukayo Saka all ruled out with injuries, Arsenal's makeshift attack struggled to make any impact against West Ham.

Arteta refused to use the injuries as an excuse though.

"No, I refuse that completely because I am talking about the standards of the players and the team that we had today, me included. And that was nowhere near the levels that we have to hit to have the opportunity to win a Premier League."

Arteta can now only hope that Manchester City do them a favour on Sunday and that his side can respond away against third-placed Nottingham Forest on Wednesday.

"Honestly, I think we have to look in the mirror at ourselves of what we can do better," Arteta said.

"First of all (we have to) suffer for 24 or 48 hours, suffer and feel the pain and make sure that we come back to training on Monday with that bite and that anger still in the stomach for Wednesday."

On the title race, Arteta said: "It's not in our hands. For me, I'm really, really annoyed about the things that are in our hands and we didn't do as well as we possibly could and that's the performance and the result today."

Meanwhile, Aston Villa boss Unai Emery was full of praise for newcomer Marcus Rashford, the much-maligned former Manchester United forward who has quickly made a terrific impression with his new team.

Rashford, who was signed by Villa on loan from United earlier this month, was a halftime substitute in Saturday's 2-1 victory over Chelsea on Saturday, assisting on both goals by fellow newcomer Marco Asensio.

Two months after Rashford fell out of favour with United boss Ruben Amorim -- and after months of criticism about what many called a lack of passion and effort -- the game marked the 27-year-old's best in a long while.

"(We want to) support him. Help him. Try to help him to feel comfortable here. Try to help him get confidence with us. Try to use the skill in our tactical idea, try to be demanding with him. He is in this process," Emery told Sky Sports on his approach with Rashford.

"Of course he played a fantastic 45 minutes. We now want to be consistent.

"Hopefully he is going to be important, like today, but then more and more and more. The most important for him is to try to be here with us and be confident and comfortable in a good atmosphere and this is my objective."

Rashford has looked keen to impress at Villa since his arrival, and his teammates and fans have returned the favour with a warm welcome.

His speed made him a threat up the left side throughout the second half at Villa Park as fans cheered him on.

"Very pleased (to acquire Rashford), especially the way he is performing now and with the two assists today," Villa midfielder Youri Tielemans said.

"Marcus is someone who can threaten everyone. He is very important for us in the way he plays because he gives us something different on the left-hand side.

"You could tell today every time he got the ball he was dangerous and hopefully with many more minutes in his legs he will only get better."

Former Liverpool and Tottenham midfielder Jamie Redknapp, who had been sceptical about Rashford's move to Villa, joined the chorus in heaping praise after the forward's performance.

"He was fantastic," Redknapp said on the Sky broadcast. "The Holte End (Villa Park's south stand) have a new hero.

"Rashford came on, he gave energy, enthusiasm, everything we want to see from him. The running, the desire ... he was excellent. He gave them that impetus to put Chelsea on the back foot.

"That's how to do the transfer window. That's a masterclass."