Manchester United [Images] won 3-1 at Birmingham City to reach the League Cup semi-finals on Tuesday and Wigan Athletic continued their dream season by joining them courtesy of a 2-0 home victory over Bolton Wanderers.

Two goals for Louis Saha and one for Park Ji-sung gave United their comfortable success and a place in the last four for the second successive season, while two for Jason Roberts late in the first half sent Wigan into their first major semi-final in their first season in top flight football.

United, out of Europe and nine points adrift of Chelsea in the Premiership, fielded a strong side in a competition that has suddenly become an important part of their season.

They started well and Giuseppe Rossi hit the bar in an early attack but Birmingham settled and held their own until halftime.

It all changed at the start of the second half, with the introduction of Wayne Rooney [Images] adding spark to the United attack.

The goals came from less familiar sources, however. Injury-ravaged French striker Saha slid in to convert a Cristiano Ronaldo [Images] cross two minutes after the restart and then turned provider as he set up Korea midfielder Park to shoot home his first goal for the club.

PLAYED WELL

Saha, whose season began a month ago following a string of injuries, then smashed in the third in the 63 minute before Jiri Jarosik headed a consolation for Birmingham in the 75th.

"I'm satisfied, I thought we played well," United manager Alex Ferguson told Sky Sports TV.

"I'm delighted for Park, he's been ever so close a few times and he deserved it."

Looking ahead to the semi-finals of a competition United have won only once, the Scot added: When the opportunity is there you must take it.

"Last year I thought we were very unlucky against Chelsea. It depends on where we are, which team I will play in January, but we will certainly give it a good shot."

Wigan, who ended a run of five successive league defeats with a 3-0 win over Charlton on Saturday, continued their recovery with an impressive victory over a Bolton side fresh from beating Everton 4-0 in the league.

Roberts turned the match late in the first half, firing in the opening goal from 10 metres out after 40 minutes and doubling Wigan's tally with a similar effort five minutes later.

Bolton looked more lively after the break and only a great save by Wigan keeper Michael Pollitt denied substitute Ricardo Vaz Te a goal after 66 minutes.

Wigan held out to register another memorable success in what has already been the greatest season in the club's history.

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