Arsène Wenger plans to talk to Mesut Özil about the German’s assessment of Arsenal’s season that “we mucked it up ourselves”. The Arsenal manager insisted on Friday that his players must not give up on winning the league despite Leicester’s significant points advantage.

“I will make sure they don’t feel that,” Wenger said. “The statement is not welcome, because we have to believe. No matter if it is just one chance in 100, we have to believe. We only have a real chance if we believe.

“I think the worst thing in life is to have wrong beliefs. So you have to make sure that you give absolutely your best, and at the end accept if somebody is better than you that you have given your best. We have to make sure that we play with passion until the end. That is the best way to get the supporters behind us.”

In an interview given over the international break, Özil rued points dropped against “the so-called smaller teams”.

Wenger has no objection to candour. "I have nothing against that," Wenger said. "You want to be fair and honest. But you want as well to look forward. I want these players to be rewarded. If you look at the effort they have put in since the start of the season, mentally in their work and dedication every day, you know this group deserves to be rewarded. But Leicester will say the same and Tottenham as well. There's still a good opportunity and we have to grab it now. It's now or never."

The issue that has most frustrated Wenger is a lack of efficiency, and he has urged his players to find more ruthlessness in the run-in, beginning on Saturday against Watford.

“Our biggest deficit compared to last season was the chances created and the goals scored. We have created more chances than last year and scored fewer goals,” he said.

With that in mind, the impetus that a few fresh faces have given the team recently has not gone unnoticed. The midfield has more balance with Mohamed Elneny passing and moving smartly alongside Francis Coquelin, and Alex Iwobi and Danny Welbeck have made a refreshing impact up front.

Wenger is particularly impressed at how a change in Welbeck’s attitude is reaping rewards.

“I think it’s not physical, it’s mental,” he said. “He looks like he realised he has to add something to his game. Maybe he was frustrated as well to be out for the first time for a long, long period. It has loaded his mental determination . . . Danny has all the qualities you need in the modern game. He has pace, he has stature. If he adds that finishing quality, he has all you need.”

Welbeck is in his mid-20s, and it is unusual for a player to improve his finishing then, but Wenger thinks the former Manchester United forward can become more ruthless.

"It is a bit unusual, but I have seen it before, especially from players who moved from the flanks to the middle. We have seen it with Pierre-Emerick Aubameyang, now at Dortmund – he was a very poor finisher on the flank. We have seen it with Thierry Henry, " he said. "Hopefully we will see it with Welbeck as well. Mentally, he looks ready for the challenge."

Welbeck's profile is more athletic than that of Arsenal's usual line leader, Olivier Giroud, and the team have looked more mobile since the England forward has been selected in the centre of attack. The onus is on Arsenal to be clinical if they are to keep believing they can maintain any long-shot pressure on Leicester.

– Guardian service