English Premier League giants Manchester United and Arsenal approach today's fourth round of group games knowing that if results go their way, early passage to the Champions League last 16 is assured.
Both clubs top their respective groups after a spotless campaign so far with wins in their opening three matches.
United need to win or draw against Dynamo Kiev at Old Trafford and hope Sporting Lisbon fail to take all three points from Roma in Group F to seal their place in the knockout stage.
And midfielder Owen Hargreaves is hoping for double cause to celebrate, the England international keen to mark his European debut for his new club by helping United through to the next round.
Hargreaves, a European champion with Bayern Munich, assessed today's assignment, telling the Manchester Evening News: "They [Dynamo] were quite poor over in Kiev. In fact I thought they were surprisingly poor for a Champions League team. To concede four goals at home is very rare at that level."
"I am sure they will try better here to redeem themselves a bit but it is a game at Old Trafford for us and we are expected to win it. If we do that we should be through to the next round. That will be our goal on Wednesday," he said.
Arsenal's Group H fate lies in their hands.
The Gunners are in action at Slavia Prague, the Czech club they hit for seven a fortnight ago at the Emirates Stadium.
That lopsided result equalled the record Champions League victory but even a more modest scoreline will suffice in Prague with a draw enough to put Arsene Wenger's Premier League leaders into the next round.
Wenger has warned his side against the dangers of complacency generated by their seemingly impregnable position.
"We want to qualify as quickly as possible, and can achieve that at Slavia Prague. The players may think we just need to turn up at take the points, but on the other side they will really have a huge desire to show that the result at Emirates Stadium was an accident," he said.
"We know it can be extremely difficult away from home. Slavia will certainly be up for it and have a huge desire to put that right again," Wenger said.
"It is not because of the quality of the players, but sometimes a team loses a bit of certainty about the way they play and their results," he said.
Slavia's slim hopes against Arsenal suffered a serious blow on Sunday as it was revealed the Czech league's leading scorer Stanislav Vlcek would miss the match.
The 32-year-old Czech international striker suffered an injury during Saturday's 1-0 win over FK Teplice.
The other Group H fixture sees second-placed Sevilla at home to Steaua Bucharest.
Arsenal's conquerors in the 2005-2006 final, Barcelona, host Rangers at the Nou Camp with Frank Rijkaard's side out to break the stalemate after their visit to Ibrox last month resulted in a 0-0 draw.
Only goal difference splits Barcelona and Rangers at the top of Group E and victory for either side, and defeat for Lyon against Stuttgart, would see them book their last 16 ticket with two games to spare.
Jean-Claude Darcheville believes Rangers can cause an upset in the Catalan capital.
The Frenchman, who returned from injury in Gers' 2-0 win over Inverness on Saturday, told the Daily Record: "I thought we would win in Lyon and we are capable of getting a good result in Barcelona. When they came here they didn't have a lot of chances to score. I think it is very important that we play with our heads in the Nou Camp. It is vital we defend very well at the beginning. If we do that we have every chance of scoring a goal afterwards."