1. Chelsea's over-reliance on Torres
Carlo Ancelotti picked his £50m striker Fernando Torres, apparently for the sole reason that Roman Abramovich has not spent a fortune to watch him warming his backside on the substitutes' bench.
Nicolas Anelka, with seven goals in the Champions League, would have been a more logical option on purely footballing grounds. Torres showed a far greater hunger for the ball than he has done in recent games, perhaps encouraged by the sight of his favourite defender Nemanja Vidic in the opposition.
But having changed the whole balance and shape of his team to accommodate Torres, Ancelotti desperately needs the Spaniard to start scoring. It almost came with a header in the 71st minute, but Edwin van der Sar pulled off a fine save. The clock now stands at 617 minutes for Torres at Chelsea without a goal.
Torres did at least look sharp, playing a slightly deeper role behind Didier Drogba. However his influence paled in comparison to the colossal impact of Wayne Rooney for Manchester United.
Ancelotti further put his faith in the struggling Spaniard when he took off Drogba for Anelka, even though the Ivorian had been getting the better of Patrice Evra.
2. Carrick won battle with Lampard
The midfield contest between Frank Lampard and Michael Carrick, two graduates of the West Ham academy, was one of the more compelling sub-plots being played out last night.
Great things were expected of both of them when they left the East End, but only Lampard can truly be said to have fulfilled his potential. Their international records tell their own story. Lampard, 32, made his England debut in 1999, and has gone on to win 85 caps; Carrick, 29, made his debut in 2001, and has so far managed just 22.
Carrick has moments when he looks like a world-class performer; the problem is those are too few and far between. Lampard in contrast has been the very definition of consistency for the past decade. The honours however went to Carrick in last night's contest.
He was excellent throughout, his highlight being the magnificent 50-yard pass to Ryan Giggs to set up Rooney's goal. Lampard, in his 500th game for Chelsea, was below his best, and missed a simple chance from three yards when he mishit his shot and allowed Evra to clear off the line.
3. Valencia's return gives United more firepower in attack
Antonio Valencia earned his place in last night's starting XI ahead of Nani with his influential display in Saturday's victory at West Ham. The Ecuador international's return after suffering a badly injured ankle has been a timely one for Sir Alex Ferguson, who has singled out Valencia for praise in recent weeks.
He started on the right of midfield, and was immediately in the action, challenging Ashley Cole straight from kick-off. Valencia's desire to get to the byline kept Chelsea on their toes, and made him a far more threatening presence than his opposite number Ramires, whose primary role is containment. When Rafael da Silva went off early in the second half following a heavy challenge by Drogba, it was Valencia who dropped back to right-back to cover, allowing Nani to fill the space in front of him.
4. Ferdinand has plenty in the tank
It was like he had never been away as Rio Ferdinand took his place in United's back four. Making his first appearance since picking up a calf injury warming up before the game against Wolves in February, Ferdinand slipped straight back into the side without the hint of a wobble.
His composure in face of some concerted Chelsea pressure was one of the reasons United won at Stamford Bridge for the first time in nine years to take a decisive advantage in this quarter-final.
Whether it was the swift feet of Torres or the muscular brawn of Drogba, Ferdinand smothered the danger with his customary cool.
5. United have the experience to complement their desire
Both managers talked of their respective team's desire to win the Champions League before this tie, and that was clear on the pitch. United have the experience of having been there and done it before. Victory in the penalty shoot-out in Moscow in 2008 gives them a psychological edge.
As the clock wore down, there was a greater desperation about Chelsea's play. They were unlucky not to be awarded a penalty in stoppage time when Evra brought down Ramires, but overall United showed greater quality and composure in the key moments of the game.