Starlet Theo Walcott followed up his midweek goal at Leeds with another at the New Den before Ricardo Fuller added a second to hand Southampton all three points against 10-man Millwall.

The 16-year-old created history at Elland Road on Tuesday night by becoming the youngest Saints goalscorer on his full debut in the 2-1 defeat - the first loss in 12 Coca-Cola Championship games for Harry Redknapp's side.

His was a tidy finish after 18 minutes, flicking the ball into the bottom corner after using his blistering pace to beat Millwall goalkeeper Andy Marshall to the ball.

Fuller doubled the advantage seven minutes later when he stooped to head Djamel Belmadi's free-kick past the outstretched arm of Marshall.

Millwall, without a home win this season, started the brighter and almost took the lead in the seventh minute when Ben May unleashed a right-footed effort from range, but the young striker's shot came back off the post with Antti Niemi well-beaten.

Nigel Quashie provided the visitors' first attempt on goal soon after but his shot from just outside the area sailed wide of the target.

It was not long before Southampton did find the mark though, and Walcott was the goalscorer - latching on to a through-ball that looked like it might carry through to Marshall, but his pace got him there ahead of the Lions goalkeeper and the Saints' record-breaker neatly flicked the ball into the bottom corner.

Fuller made it two with his third goal of the season in the 25th minute following a foul by Millwall defender Philip Ifil on Quashie.

Ifil was booked for the infringement before the Jamaican headed home Belmadi's cross from the resulting free-kick.

Belmadi almost made it three on the half-hour mark, but was unfortunate to see his long-range drive rebound off the post.

Ifil, on loan from Barclays Premiership Tottenham, added to Millwall's woes on the stroke of half-time when he received his marching orders for a second bookable offence after felling Danny Higginbotham.

The second half began in much the same way as the first - with May firing in a shot from range - but this time his effort did not cause Niemi too much cause for concern and the Finland international easily dealt with the danger.

Just after the hour mark substitute Carl Asaba - returning to action after sustaining a shin injury in last weekend's draw with Norwich - stung Niemi's palms from the edge of the area.

Saints fans were forced to wait until the 75th minute for their side's first effort of the second half, but Belmadi shot over the crossbar from the edge of the area.

May again tested Niemi in the closing stages but Southampton emerged victorious to record only their second away win of the campaign.

Meanwhile Millwall have not won at home since 24 April when goals by Peter Sweeney and Barry Hayles gave the Lions a 2-1 win over Preston.

Teams:

Millwall Marshall, Ifil, Lawrence, Williams, Vincent (Paul Robinson 28), Wright, Dunne, Morris (Asaba 45), Livermore, May, Hayles.

Subs Not Used: Hutchison, Braniff, Jones.

Sent Off: Ifil (45).

Booked: Williams, Ifil.

Southampton Niemi, Cranie, Lundekvam, Svensson, Higginbotham, Belmadi, Oakley (Wise 68), Quashie, McCann, Walcott (Kosowski 65), Fuller (Jones 58).

Subs Not Used: Smith, Delap.

Booked: Svensson, Fuller, Quashie.

Goals: Walcott 18, Fuller 25.

Att: 10,759

Ref: C Foy (Merseyside).