Avram Grant will have to win the Barclays Premier League title or the Champions League to retain his position as the Chelsea first-team coach. His team followed last month’s Carling Cup final defeat by losing their FA Cup sixth-round tie away to Barnsley 1-0 on Saturday, passing up the opportunity to walk through a weakened field after Manchester United’s defeat by Portsmouth earlier in the day. It is the first time since 1987 that none of the “big four” have featured in the semi-finals.

Grant opted to leave Didier Drogba and Frank Lampard at home to recuperate from slight knee and groin injuries respectively. Kayode Odejayi, whose only previous goal for a team four points above the relegation zone in the Coca-Cola Championship came against Scunthorpe United in September, scored midway through the second half of an epic tie at Oakwell.

Neither Roman Abramovich, the Chelsea owner, nor Peter Kenyon, the chief executive, attended the match, preferring to watch it on television. It is thought that there is some disbelief over Grant’s team selection in a competition that was seen as Chelsea’s to lose by senior figures at the club.

Coming only a fortnight after the 2-1 defeat by Tottenham Hotspur at Wembley, Grant is under severe pressure and it has been made clear that Chelsea will have to win one of the two remaining prizes if his reign is not to come to an inglorious halt only eight months after succeeding José Mourinho. Grant’s close relationship with Abramovich may result in him being moved to another role, but a new man is likely to be given the team selection duties.

“We must congratulate Barnsley, who showed great spirit, but for me it’s a big disappointment,” Grant said. “I always feel responsible. I never in my life put responsibility on other people. I am the manager and I am responsible for everything. Since I came to Chelsea, it’s the most disappointing day. But we will fight. We have two big competitions still and we will look to the future. At all times when you are at a club like Chelsea there is pressure.”

Nicolas Anelka, who deputised for Drogba up front, tried to deflect the pressure from Grant. “I think the criticism has to be aimed at the players,” the striker said. “We didn’t do what we had to do. We did not play well. We know the media will be after the manager, but as a player you know when you have played well and we did not play well.

“We have spoken about the Champions League before and we will try our best to win it because when you look around the dressing-room we have big players who have the qualities to do it. I think Barnsley will be forgotten if we win the Champions League.”

Martin Devaney, who set up Barnsley’s winning goal, has appealed to the FA to take the emotion of the occasion into account before deciding whether to penalise the club for the fans’ pitch invasions either side of the final whistle. “It was a bit silly but you can understand them being excited,” the winger said. “It’s a massive day for Barnsley and a great achievement. I think the FA have got to take that into consideration.”

It is understood that the FA will give Barnsley a week to compile a report proving that they did all that could reasonably be expected in terms of crowd control. “Coming on to the pitch is a criminal offence and we would expect the club to work with the police with respect to anyone who was arrested,” an FA spokesman said.