Terry Yorath will hand Pablo Bonvin a personal vote of thanks should the Sheffield Wednesday board appoint the former Wales international as their new manager.
The Argentinian striker scored the winner for the second successive match to give Yorath a 100 per cent record as caretaker since Peter Shreeves' resignation a week ago.
After sealing a victory against Walsall on Saturday with a last-minute strike, Bonvin – on loan from Boca Juniors – this time provided a crisp 58th-minute finish to lift Wednesday out of the bottom three.
In condemning Barnsley to an eighth league defeat, and to one place off the bottom of the First Division, the pressure is mounting on manager Nigel Spackman.
His cause was not helped by the 65th-minute dismissal of Carl Regan for a reckless challenge on Owen Morrison, allowing Bonvin to make 10-man Barnsley pay as he added his second and his side's third eight minutes from time.
Isaiah Rankin had already missed a sitter two minutes previously after being set up by Kevin Gallen, before the latter fired a stunning right-foot 20-yard volley past Kevin Pressman into the top left-hand corner from a Lee Crooks free-kick.
Gerald Sibon then headed home his fifth of the season midway through the half to haul Wednesday level.
Bonvin , having gone close twice previously, was not to be denied and 13 minutes after the interval he latched on to a Steven Haslam through ball before lashing an 18-yard shot beyond Marriott.
Regan's dismissal, 20 minutes after coming on at half-time, only added to Spackman's misery and Bonvin sealed a night of triumph for Wednesday with his fifth goal of the season.
Sheffield Wednesday: Pressman, Hendon, Geary, Westwood, Maddix, Quinn (Donnelly, h-t), Soltvedt, Haslam, Morrison (McLaren 90), Bonvin, Sibon (Di Piedi, 85). Substitutes not used: Stringer, Crane.
Barnsley: Marriott, Crooks, Barker, Morgan, Barnard (Regan, h-t), Donovan, Lumsdon, Oster, Sand (Tinkler, 59), Rankin (Jones, 65), Gallen. Substitutes not used: Ghent, Gorre.
Referee: M Messias (York).Reuse content