If there is one consequence of Chelsea's win over Barcelona on Wednesday that no manager involved in the battle to secure a Champions League place has missed, it is the possibility that securing fourth in the Premier League this season might not be good enough for entry into Europe's elite competition.
The prospect of Chelsea finishing outside the top four but winning the Champions League, as Liverpool did in 2005, remains a long shot but then long shots are what managers are paid to keep their eye on. Arsène Wenger acknowledged as much yesterday and it means that a win for Arsenal in today's lunchtime kick-off against Chelsea carries even more significance than it might have done before Wednesday's semi-final first leg at Stamford Bridge.
Of course, a demolition of Chelsea at the Nou Camp in three days' time and all that talk ends but should Chelsea make it to the final in Munich then the picture changes. When Liverpool won the trophy in 2005, special dispensation was made to allow five English clubs to enter the competition the following season. From then the rules were tightened so that a defending champion who finishes outside the top four takes precedence over the team that finishes fourth.
Wenger had forgotten the 2005 conundrum – perhaps because in those days, what happened beyond first and second scarcely concerned him. "It's right the Champions League winners have the right to defend the trophy," he said. "That it takes the fourth place is unfortunate. Ideally, you would like to combine the two. The team who finish fourth have fought the whole season and cannot get into the Champions League. I find it right the winners have the right to defend the trophy."
What if it were Arsenal in fourth place who lost out to a Chelsea team that won the Champions League? "We would not be happy but it's the rules and we have to accept it. We cannot change the rules just because it's us."
His team go into today's game having lost their last match at home to Wigan, while Chelsea beat the European champions. Wenger was surprisingly complimentary about Chelsea's approach to the Barça game – "They were very good at what they decided to do and they decided to defend" – but he had little sympathy for Roberto Di Matteo's four games in 10 days.
"It's part of being successful. We have done that many times. Sympathy? You have some... but it's part of wanting to be at the top level. It was the same when we played Milan at home [on 6 March] and our players were on international games in Africa. We played Sunday at Tottenham, [they played a] Wednesday international, Saturday morning at Liverpool and Tuesday night at Milan and some of the players played the full games.
"[Against Barcelona] Chelsea had a game-plan that worked a little bit. Maybe they were lucky because they hit the woodwork twice. I feel Chelsea played the system they wanted to play well. The three central midfielders did well, the two wide players worked very hard and Gary Cahill and John Terry had a great game. The two of them they blocked some shots from [Lionel] Messi and were remarkable sometimes. They had a great performance on the day. With what they wanted to do. And [Didier] Drogba did the rest..."
Drogba is not expected to play today with a knee injury picked up on Wednesday and Wenger only alluded to his true feelings about the Chelsea striker's performance. "He [Drogba] was good in everything he did," Wenger said, "he did even more than expected."
The 5-3 win at Stamford Bridge in October was, for a long time, the stand-out result of Arsenal's season, until they put together that run of seven wins in nine league games which included a defeat of Manchester City at the Emirates. In fact, had Chelsea not had their worst season since the Roman Abramovich era began in 2003, Wenger's problems might have been seen in an even more unforgiving light.
His team beat Barcelona at home last season before losing in the Nou Camp, albeit after the dismissal of Robin van Persie. Arsenal's approach to their home game against Barça was very different to that taken by Chelsea although Wenger said Arsenal had played the same way in the 2005 FA Cup final win over Manchester United.
Both clubs find themselves in stronger positions than when they met in October and Abou Diaby, who has played three games all season, the last in March, is back in the Arsenal squad. In many respects the season has finally come alive for both clubs, although they know that it is laying the foundation for Champions League football next season that is the imperative.