Sir Alex Ferguson has reiterated his belief that David de Gea will recover from his difficult start at Manchester United and insisted he was not worried about playing the Spaniard behind a new, experimental defence now that Nemanja Vidic and Rio Ferdinand are both injured.

Ferguson intends to keep faith with De Gea despite the goalkeeper's mistakes in the Community Shield and last weekend's game at West Bromwich Albion, with the £18.3m goalkeeper lining up against Tottenham Hotspur on Monday behind a defence featuring Chris Smalling at right-back with Phil Jones and Jonny Evans in the centre-half positions.

That quartet have an average age of 21 years and five months going into a run of eight games that will also feature Arsenal, Chelsea, Manchester City and Liverpool, but Ferguson has a long record of placing his trust in the club's younger players and he is backing them to show they can cope.

"The responsibility will lie with Jones, Evans, Smalling and De Gea," he said. "They are young, they don't have the experience of Ferdinand, Vidic and [Edwin] van der Sar, but they have the potential and they have the temperament and the courage to play."

De Gea, he said, will have learned "by experience of the games he has had so far" and there was a vote of confidence, too, for Evans, whose last season was difficult. "Evans has got ample experience, he's been at the club since he was 12. He's played plenty of first-team games."

Jones, the youngest player at 19, will be making his first start for United in a competitive match, with Vidic expected to be out for five weeks because of a calf injury. The prognosis for Ferdinand is better, his hamstring strain is not as serious as first thought and he could be back against Arsenal next weekend and even has an outside chance of facing Tottenham, an update thatwill also represent good news for the England manager, Fabio Capello.

"Top level players with experience are vital but we don't have them [Ferdinand and Vidic] and we are confident in the players who are replacing them," Ferguson continued. "Jones has experience of playing for Blackburn last season. He and Smalling, I thought, were the stars of the European Under-21s [Championship]. Smalling had a fantastic season last year and has continued his progress so I have absolutely no issues whatsoever.

"I don't see it as a challenge for these young players; it is a responsibility. It is an important position they are in but they have the ability and the temperament, so I don't see it as a worry for me at all. I see it more as something I am looking forward to, rather than worrying about it.

"At some point when the young players may hit a pocket there will be enough experience to augment the challenge we're after this year. It is a very young team at the moment, but it's one full of energy and of great ability, and I'm enjoying watching them."