United clinch top spot

Already qualified from their pool, the Red Devils fell behind when Tomasz Kuszczak allowed Abel's driven cross-shot from the right touchline to beat him at his near post in the 21st minute.

But Carlos Tevez, on as a half-time substitute, was credited with the scrambled equaliser before Ronaldo scored his last-ditch winner from 25 yards out.

After his one-man mission to inflict more damage on Sporting Lisbon appeared certain to end in frustration, Ronaldo stepped up to drive home a 25-yard free-kick in the second minute of stoppage time.

Sir Alex Ferguson looked like being frustrated, having only Carlos Tevez's leveller to show for their second half efforts after a woeful opening period saw Abel put the visitors in front and had them threatening what would have only been United's eighth home defeat in European competition.

Instead, Ronaldo produced a touch of class when it mattered and not surprisingly, Tomasz Kuszczak was the first one to congratulate him at the final whistle.

Kuszczak's blunder may not be dissected in quite the same manner as Scott Carson's inexplicable failure to keep out Niko Kranjcar's speculative shot at Wembley last week but if anything, the ramifications could be more serious, for the player at least.

Abel deserves plenty of credit for the way he spotted the opening, then curled a superb shot in at the near post with the outside of his left foot from the right touchline.

However, Kuszczak could not escape blame, for it was his blatant anticipation of a cross which provided Abel with the space to finish.

The United breakthrough eventually came thanks to Patrice Evra's scampering left-wing burst. Tevez knew little about it as Ronaldo's mis-hit shot from Louis Saha's lay-off arrived at his feet but a firm deflection off the South American was enough to see United level.