Manchester United's Cristiano Ronaldo, left, vies for the ball against Tottenham's Didier Zokora, right, during the Carling Cup final at Wembley stadium on Sunday.

Manchester United took the first step toward an improbable quadruple this season, beating Tottenham in a penalty shootout to win the Carling Cup on Sunday at Wembley Stadium.

It wasn't easy for the Red Devils, despite facing the much weaker Spurs, a side only two points from the relegation zone. Tottenham played United tough all day, and had several chances to break the 0-0 deadlock.

But the score remained level through full time and 30 minutes of extra play. United midfielder Cristiano Ronaldo had a glorious chance to win it in the 90th minute, slinking through Spurs' defence before knocking a shot off the woodwork.

Earlier in the second half, the 2008 FIFA world player of the year was brought down by Ledley King in the box, but instead of a spot-kick, Ronaldo was given a yellow card for diving.

He got his chance when the game went to penalties, and he made no mistake, burying his shot past Spurs goalie Heurelho Gomes. United hit the target on all four shots they took, while Tottenham missed two of three.

The EPL leaders were also resting a few key players, with striker Wayne Rooney and starting goalkeeper Edwin van der Sar among others cheering from the touchline.

United is in contention for an unprecedented four major trophies this year. The Red Devils are safely atop the league standings with the season winding down, they are on pace to reach the quarter-final of the Champions League, and they're still in the FA Cup competition.

Add to that a FIFA Club World Cup won back in December, and it could be a dream season for United, maybe even better than their 1999 treble-winning campaign. 

"There's a long way to go, but we've just got to keep the same desire," said United captain Ryan Giggs during the celebrations.