Manchester United and Manchester City can both seal their places in the knockout stages of the Champions League with victories over Benfica and Napoli respectively on Tuesday.
They could be joined in the last 16 by German giants Bayern Munich, who need just a point at home to pointless Spanish side Villarreal, 2010 champions Inter Milan, who also need a point at Turkish side Trabzonspor, and Dutch side Ajax if they beat Lyon.
Both United and City face tough tasks nevertheless to secure their places as Benfica are equal on points with the former while Napoli gave City a fright in their opening match - a 1-1 draw at City - and are tough to beat at home.
United warmed-up for the visit of Benfica with a 1-0 win away at Swansea to keep the pressure on City at the top of the Premier League.
However, what really pleased Sir Alex Ferguson was the manner in which his defence performed after a series of worrying slips in recent weeks. "Keeping clean sheets has been an integral part of our success and we have been careless with our defending," the 69-year-old Scot told MUTV.
"A few weeks ago there was genuine criticism about the defending and the chances opponents were getting.
"It was a solid performance. When you win these games 1-0 it brings the concentration back to a good level which has been lacking. The concentration we showed is exactly the concentration we need back in the team," he said.
Ferguson was also delighted in that he had a surfeit of choices in terms of selection for Tuesday's match.
Benfica - who held United 1-1 in Lisbon - will have to achieve something no other Portuguese side has done before in 10 Champions League matches at Old Trafford - namely win there.
However, they are yet to lose away from home in Europe this season.
Manchester City will also have to pull off quite a feat to prevail in Naples as the hosts are unbeaten in all 10 European matches they have contested since returning to continental competition in 2008.
However, City manager Roberto Mancini believes his side are acclimatising to the higher level of the Champions League, though, he accepts that his opponents will not be a pushover.
Bayern are three points clear of Manchester City at the top of Group A, with Villarreal bottom of the table after four defeats and the best the Spaniards can now hope for is to finish third and qualify.
However, Bayern have shown signs recently of a drop in their form. Despite having gone 13 games unbeaten up until the end of October, Bayern have struggled since losing star midfielder Bastian Schweinsteiger with a broken collarbone at the start of November.