Gardner scored twice at The Willows
Salford: (12) 20
Tries: Littler, Wilshere 2
Goals: Wilshere (4)
St Helens: (28) 32
Salford look destined for relegation after failing to take advantage of a weakened St Helens at The Willows.
Tries: Gardner 2, Gidley, Graham, Cunningham
Goals: Tyrer (6)
With an eye on next week's Challenge Cup final, Saints started the match without six regulars and trailed 14-12 early in the second half.
But two tries in four minutes from James Graham and Keiron Cunningham knocked the stuffing out of Salford.
Salford are three points adrift of Hull KR and must win two of their last three games to have a chance of staying up.
Saints remain top of Super League, level on points with Leeds.
Salford coach Shaun McRae:
"We have still got to win at least two of our remaining games. "If we can play like we did tonight in the next three matches, we have got wins in us. There is no doubt about that.
"I thought it was a tremendous effort and maybe, with an ounce of luck and a bounce of the ball here and there, it could have been a different result.
"In the last few weeks I've been critical of my team but tonight we gave as good as we got.
"I'm disappointed with the result because I thought we put in enough effort to get something out of the game."
Saints coach Daniel Anderson:
"Two points are very important at this stage of the year.
"We knew they were desperate but we just had some big plays from some very experienced players at the end of the game.
"The only injury we picked up was to one of our youngsters, Chris Dean, who hurt a shoulder on his debut. Everyone else is alright."
Salford: Salford: Fitzpatrick, Hodgson, McGuinness, Moule, Barnett, Wilshere, Robinson, Leuluai, Alker, Korkidas, Littler, Sibbit, Turner. Replacements: Dorn, Highton, Gower, Nash
St Helens: Gidley, Gardner, Tyrer, Gilmour, Meli, Roby, Smith, Fozzard, Cunningham, Cayless, Bennett, Clough, Flannery. Replacements: Graham, Hargreaves, Moore, Dean.
Referee: Ian Smith (Rotherham)