Arsene Wenger has put his faith in goalkeeper Lukasz Fabianski ahead of the first leg of Arsenal's UEFA Champions League last 16 tie with Porto.
Regular No.1 Manuel Almunia has been ruled out of Wednesday night's game in Portugal due to a finger injury, meaning Fabianski will start.
Fabianski has made just five appearances this season after missing the start of the campaign due to a knee injury and has yet to feature in the Premier League this term.
However, he played in last season's Champions League quarter-final win over Villarreal and Wenger is confident the Poland international can competently replace Almunia.
"I believe that Fabianski is top, top level and has massive potential," said the Arsenal boss.
"It is not easy for a keeper to come in and out.
"What he misses at the moment is the number of games, but I have no doubt about his potential."
In addition to being without Almunia, the Gunners are also missing Eduardo, William Gallas, Alex Song and Andrey Arshavin, as well as long-term absentee Robin van Persie.
Wenger, though, insists being low on numbers should not be an issue for the Premier League side, who did not have a game at the weekend.
"It is difficult to say how long they will be out," said Wenger. "But it is not a serious concern.
"The concern is that the players who are here perform at their best.
"It is part of the season that you do not always have all the players available to select the team, but I am not bothered by that."