Arsène Wenger has said Chelsea are nailed on to win the Premier League title if they continue their form, with the Arsenal manager admitting there are no serious contenders to challenge José Mourinho’s side on the evidence of the season so far. The Arsenal manager was speaking after a 2-1 defeat at Swansea left his team in sixth place and 12 points behind Chelsea after only 11 games.

Wenger bemoaned the absence of “the right rigorous attitude” after Arsenal allowed a second-half lead to slip for the second time in five days. Ahead through Alexis Sánchez’s 12th goal in his past 14 appearances, Arsenal conceded twice in three minutes. Gylfi Sigurdsson, with a majestic free-kick, scored the first, and Bafétimbi Gomis, who had been on the pitch only two minutes, got the winner to inflict Arsenal’s second league defeat of the season.

With Chelsea unbeaten and four points clear at the top of the Premier League, Wenger conceded the broader picture does not look good for Arsenal and the other clubs with title aspirations. “At the moment Chelsea are on course for 100 points this season,” he said. “If you look at the number of points they have, if they keep that up nobody will catch them, that’s for sure. There doesn’t look to be anybody capable to challenge them at the moment.”

Asked why Chelsea are so dominant while their rivals were struggling to find any sort of momentum, Wenger replied: “There is no obvious reason. They had a good start, and we have gone through that [in the past], as long as you don’t lose, you don’t question yourself, there is a little bit extra spirit in the team that, when it is tight, gets them through.”

On the back of surrendering a three-goal lead against Anderlecht in the Champions League on Tuesday, Wenger admitted it had been a particularly tough period. “We had a very disappointing week, considering the performances we produced and the end result we got it’s very disappointing. We were 3-0 up against Anderlecht and 1-0 up today and in the end we lose two points against Anderlecht and three points today. I think it’s very disappointing because you have to be capable, once you are 1-0 up and a big team, to win the game.”

Arsenal would have gone into the top four with victory but instead Garry Monk’s side leapfrogged them and climbed to fifth place. “I felt that we allowed them back into the game by losing some challenges in the middle of the park that you cannot afford to lose,” Wenger said.

“It’s unfortunate to lose a game like that but we were not rigorous until the end. We produced quite a decent performance for 75 minutes but you have to last 90 minutes. Did Tuesday night play a part in our mind? I don’t think so. I hope not. And Swansea, you have to give them credit, they didn’t give up, they fought until the end, they scored a good free-kick, and of course that gave them momentum again.

“In the end we lost the three points, that’s very sad, very disappointing, but we have to take it on the chin because we didn’t play for 90 minutes with the right rigorous attitude.”