Arsenal cruised into the quarter-finals of the English League Cup on Tuesday as a virtual reserve team thrashed a full strength Wolverhampton Wanderers 5-1 at Highbury.

In the night's other fourth round tie Southampton deservedly beat local rivals Portsmouth 2-0 with two goals by England striker James Beattie.

Arsenal, who beat Southampton in last season's FA Cup final, advanced with ease in the lesser competition despite resting almost all their first team squad against a team second-last in the premier league.

"We had a mix of younger and experienced players and I must congratulate both," Arsenal manager Arsene Wenger told Sky Sports.

His exasperated opposite number Dave Jones said: "That's not what I expect from a Wolves side.

"We knew we were going to be in for a tough game whatever side they put out but if the players are not applying themselves you are not going to win anything."

French striker Jeremie Aliadiere got the opening goal in the 24th minute and Nwankwo Kanu found the target from close range in the 68th.

Arsenal then turned on the style as Aliadiere curled in his second and Sylvain Wiltord weighed in with his first goal since August.

Alex Rae pulled one back for Wolves with a spectacular finish but Arsenal had the last word as 16-year-old Spanish forward Francesc Fabregas became the club's youngest-ever scorer two minutes from time.

There was further good news for Arsene Wenger as midfielder Patrick Vieira came through unscathed in his first full game since he suffered a thigh injury at the end of September.

Portsmouth's first appearance at St Mary's Stadium -- the first south coast derby for almost eight years and only the 30th meeting of the two teams in almost a century of rivalry -- proved to be something of a damp squib.

Beattie poked in the opening goal in the 33rd minute to end Southampton's a run of four scoreless games and got his second with an injury-time penalty after Portsmouth's Dutch defender Arjan De Zeeuw brought him down and was harshly sent off for the offence.

"We've scored goals, kept a clean sheet and we are through and that's about it," said Southampton manager Gordon Strachan.

The six remaining fourth round games are played on Wednesday when holders Liverpool face Bolton Wanderers and last year's beaten finalists Manchester United take on West Bromwich Albion.