London - Per Mertesacker admits Arsenal must build on their crucial Champions League victory over Bayern Munich and develop more consistency if they are to sustain their Premier League title challenge.
A victory over Everton at the Emirates Stadium on Saturday would move Arsenal to the top of the table, 24 hours before current leaders Manchester City face neighbours United in Sunday's cross-town derby.
Yet despite a largely positive start to the campaign, Arsene Wenger and his players have still come in for criticism for a number of underwhelming displays, particularly in Europe.
But since a shock loss to Olympiakos, the Gunners have recorded back-to-back, three-goal Premier League victories over Manchester United and Watford before inflicting a first defeat of the season on German champions Bayern, who were beaten 2-0 at the Emirates on Tuesday.
Wenger's side have shown their qualities in recent weeks, but Gunners centre-back Mertesacker insists the challenge now is to maintain those standards.
"We want to play a part in the title race. We need to have a certain consistency otherwise it will be difficult," Mertesacker said.
"But if you get good wins against the good teams then it breeds confidence.
"We had a bad start against West Ham on the first day of the season, so it took us a bit longer to get going but the League is very competitive. You can see that consistency is hard to come by."
Arsenal's efforts to string together a run of good results will not be helped by the loss of Aaron Ramsey to a hamstring injury.
Ramsey hobbled out of the Bayern clash and Wenger expects the Wales midfielder to be out for at least a month.
Wenger directed some of the blame for Ramsey's injury towards his player's commitments with Wales, who selected him for a meaningless fixture against Andorra after qualification for Euro 2016 had already been secured.
"He had a scan today (Thursday) but he's out. I believe he will be out until after the next international break," Wenger said.
"With the last international break, the fact that he played against Andorra certainly cost him."
Wenger also admits it will be the new year before Danny Welbeck, Jack Wilshere and Tomas Rosicky are fit again.
Everton have not beaten Arsenal away from home since January 1996 - a statistic manager Roberto Martinez will be keen to change.