Preston went ahead in the 52nd minute through Scott Sinclair but with three minutes to play, McManaman found the back of the net with the Hatters’ first shot on target.
The Sky Bet Championship fixture was contested behind closed doors in the first game week back since the coronavirus pandemic halted matches in March.
All 22 players and the officials paid their respects to the NHS and those who have lost their lives during the coronavirus pandemic in a one-minute round of applause at the start of the match, as well as taking the knee upon the referee’s whistle in unity with the Black Lives Matter campaign.
On a hot and sunny afternoon at the Kenny, there were few clear-cut chances for either side during the first half, but the away side had the more presentable opportunities.
Sean Maguire came close from the edge of the box during the early stages and the Republic of Ireland international was later denied by Simon Sluga, who hurried off his line to make himself big and block his effort behind.
Preston took the lead seven minutes after the half-time restart as Sinclair slid the ball past Sluga after being played through by Tom Barkhuizen.
The away side seemed to be heading home with all three points until McManaman produced a moment of brilliance in the 87th minute.
In typical fashion, McManaman came off the bench to score a late goal – his fourth of the season and without doubt his best one yet. Fellow substitute James Bree squared the ball to the former Wigan man 25-yards from goal and with a couple of touches forward, the 29-year-old found the top corner with a superb finish.
Luton were in the ascendency after the goal and Ryan Tunnicliffe came close with an audacious long-range effort which curled just over the bar.
Six minutes were added on at the end of the game, though neither team could find a winner and the Hatters now turn their attention to an away trip to Swansea City having closed the gap to five points despite dropping to the foot of the Championship.
TOWN: Sluga; Cranie (Bree 75), Carter-Vickers, Pearson (Bradley 84), Potts; Tunnicliffe, Rea (C) (Moncur 75), Mpanzu, Brown (McManaman 75); Cornick, Collins (Hylton 84).
Subs not used: Shea, Lee, Shinnie, Butterfield.
Yellows: Rea
Goal: McManaman (87)
PRESTON NORTH END: Rudd, Browne, Davies, Bauer, Hughes, Pearson, Gallagher (C) (Fisher 77), Johnson, Sinclair (Potts 77), Barkhuizen, Maguire (Nugent 65).
Subs not used: Ripley, Storey, Ledson, Harrop, Bodin, Stockley
Goal: Sinclair (52)
Referee: John Brooks