Archer, playing on the wing, set up the first and scored the third during what was his best performance since joining Saints.
His contributions helped Saints earn a seventh successive win and extended their unbeaten run to 18 games, moving them to fourth.
Here’s how we rated every Southampton player’s performance against Blackburn on Tuesday evening…
Daniel Peretz – 7.
Will be pleased with another clean sheet, although he was rarely tested all night. Produced three saves, all of which were rather routine.
James Bree – 7.
Gave Blackburn nothing down the left-hand side before he was withdrawn at the break for a well-earned rest. Expect him to be back in the starting lineup at Swansea.
Taylor Harwood-Bellis – 8.
One loose pass was the only blot on a brilliant performance that saw him play at centre-back in the first half and right-back in the second. Won all of his duels.
Jack Stephens – 8.
Also deserves credit for limiting Blackburn to very few genuine chances. Won all of his ground duels and made over 100 passes. Came close with a first-half headed chance.
Ryan Manning – 7.
Credited with Southampton’s goal, which he scored by following in on the ball as it pinged around the box. Was not at his best from open play crosses, but remained strong from set-pieces.
Cam Bragg – 7.
A surprise inclusion in the starting lineup, replacing Flynn Downes, but he delivered another good performance. Always seemed to be in the right place and showed a good range of passing.
Shea Charles – 8.
A real showcase of how much he has improved in recent weeks, especially when driving forward with the ball. Drew two yellow cards in the first 10 minutes. Won all but one of his duels. Was subbed late on when he ran out of energy.
Tom Fellows – 6.
The least effective of Southampton’s front four in attack, but continues to contribute defensively. Managed just two crosses, which is his bread and butter, before being replaced.
Kuryu Matsuki – 7.
Was deployed in his natural central role here and showed his talent for picking out a pass to set Archer away for Southampton’s opener. Fluffed a second-half chance to score on his return to the lineup.
Cam Archer – 9.
The star of the evening. This was his best Saints performance. A real threat when running at Blackburn’s defenders, delivered good crosses, and wrapped the game up with a deserved goal late on. He definitely has a future out wide.
Cyle Larin – 8.
Was clinical with his early chance to set Saints on their way, scoring his fifth in the Championship, before producing a top big-man performance. Held the ball up in the buildup to Archer’s late goal. Blackburn’s defenders couldn’t handle him.
Substitutes
Nathan Wood – 7.
Did well, which is not always easy for a defender thrust into the game at the break. A perfectly timed recovery slide tackle was the best moment of his evening.
Flynn Downes – 6.
Came on for Bragg with just under 20 minutes to go and slotted into the game without much notice.
Leo Scienza – 7.
Teed Archer for his late goal, cutting back to the winger when he had the chance to shoot himself.
Welington – 6.
Replaced Manning at left-back as he continues to build up fitness following his recent return from injury.
Jay Robinson – N/A.
No rating here as he came on with just a few minutes of regular time to go. Made his first senior appearance since January 25 at Portsmouth.