Leyton Orient suffered only a second defeat in 17 matches in League Two on a disappointing night at Plough Lane.
Having slumped to a last-gasp loss at Crewe in the FA Cup first round on Saturday, O’s came under early pressure in south west London and saw Ayoub Assal fire wide of the near post.
But the visitors grew into the game, with Ruel Sotiriou almost finding Theo Archibald and Idris El Mizouni breaking to win a corner, which was cleared.
Archibald’s first-time pass released Aaron Drinan, which led to another corner, and a quick move saw Paul Smyth set up a chance for the Irish striker, which was blocked.
Smyth won another corner, from which El Mizouni won a free-kick, but Nikola Tzanev saved the low effort from Tom James.
And the hosts then opened the scoring on 19 minutes on the break when Assal’s effort was deflected past Lawrence Vigouroux.
James picked up the first booking of the night and Sotiriou saw an attempt from a long throw-in loop wide of the target as O’s looked to respond, with Archibald receiving a warning for pushing a Wimbledon player.
Ryler Towler received Wimbledon’s first yellow card for a tackle on El Mizouni but the hosts doubled their lead on 32 minutes when Harry Pell fired into the top corner from the edge of the box.
Tempers boiled over just before the break, with Drinan booked for a challenge on a defender and Paris Maghoma cautioned on the stroke of half-time.
And O’s went close to a reply four minutes after the restart when Archibald’s effort was headed off the line by Welsh international Chris Gunter.
Sotiriou did well to win possession and tried to play Drinan in on 54 minutes, but the 24-year-old was shut out by the home defence, before Maghoma escaped a second booking for hauling down Smyth.
Smyth escaped on the left soon after and his cross into the box almost deflected into the path of Sotiriou, before Wellens made a double change on 65 minutes and sent George Moncur and Jordan Brown on for Archibald and James.
Assal and George Marsh were shown yellow cards in quick succession, before Charlie Kelman replaced Sotiriou and Vigouroux made a superb save to touch Ethan Chislett’s 25-yard free-kick onto the crossbar when it looked destined for the top corner.
O’s won a corner when Brown’s cross was blocked, possibly by a hand, and the substitute saw a shot from the edge of the box find the net only to be ruled out by an offside flag moments later.
Drinan made way for Jayden Wareham in the closing minutes of normal time, but O’s could not make much impact during six minutes of additional time as Moncur fired over and they will now look to get back on track at Harrogate Town on Saturday.
Leyton Orient: Vigouroux, James (Brown 66), Happe, Smyth, Sotiriou (Kelman 74), Archibald (Moncur 66), El Mizouni, Drinan (Wareham 87), Pratley, Beckles, Hunt.
Unused subs: Sargeant, Ogie, Duke-McKenna.