Goals from Adam Lallana and Sharp gave Adkins' team only their second victory since Boxing Day and moved the second placed Saints within one point of leaders West Ham, whose game at Peterborough was postponed due to a frozen pitch.
Southampton had gone without a win in their last four home matches, including an FA Cup exit against Millwall in midweek, but Lallana opened the scoring in the eighth minute with his ninth goal of the season.
Sharp, a three-million-pound signing from Doncaster during the January transfer window, got the second goal in the 33rd minute via a deflection off Burnley defender Ben Mee.
"He is going to be a massive threat in this league. But it is not about 11 players, we have a very strong squad to deal with the latter stages of the campaign," Adkins said.
"You can see the link-up play between Rickie Lambert and Billy, there are goals in both of them. They are going to be a huge threat for any defence.
"We have very good strikers at this football club now. There is a real belief about us now and the win sets us up nicely for the rest of the season."
Cardiff manager Malky Mackay slammed his lacklustre stars as the League Cup finalists lost ground in the promotion race with a 2-1 defeat at Leicester.
Mackay's team, who face Liverpool at Wembley later this month, suffered back-to-back league defeats for the first time this season as they followed up last week's 3-1 defeat at home to Blackpool with another poor display.
Paul Gallagher opened the scoring with a penalty four minutes before half-time and the former Blackburn forward struck again with a superb 71st minute free-kick before Peter Whittingham reduced the arrears from the spot six minutes later.
Leicester move to within six points of the play-offs, while Cardiff remain fourth but slip five points behind second-placed Southampton.
"I'm disappointed because in the first half we didn't get out of the blocks," he said.
"We were playing a good team who we didn't get close enough to in the first half and allowed them to play too much.
"You always have to be ready to match them and I don't think we did that until the second half."
Hull climbed up to fifth place with a 3-0 home win over Bristol City thanks to goals from Jack Hobbs, Robert Koren and Matty Fryatt.
Reading are one place outside the play-offs after Jimmy Kebe and Jason Roberts scored in a 2-0 win over bottom of the table Coventry at the Madejski Stadium.
Kebe opened the scoring with a deflected strike in the 25th minute before former Blackburn forward Roberts bundled the ball home from Ian Harte's corner two minutes before the break.
Alan Navarro scored in stoppage time as Brighton snatched a 2-1 win at managerless Leeds.
Luciano Becchio cancelled out Brighton striker Craig Mackail-Smith's opener but Navarro's low drive from the edge of the box went in via a deflection off Adam Smith to silence Elland Road.
Elsewhere, Millwall drew 0-0 with Derby, Nottingham Forest were held to a 1-1 draw by Watford, Blackpool drew 1-1 against Portsmouth and Ipswich's home match against Middlesbrough was abandoned due to a frozen pitch.
Source: AFP
Source: AFP