Assombalonga, who was strangely overlooked in the voting for the Football League Player of the Year Award in the division this week, scored twice in three minutes as Peterborough United beat play-off rivals Milton Keynes Dons 2-0.
Posh had early appeals for a spot-kick turned down after Assombalonga took a tumble under a challenge from MK Dons goalkeeper Martin, but nothing was given.
Nicky Ajose saw a volley from 20-yards tipped over by Martin and from the resulting corner kick, Nugent headed over from McQuoid's right-wing delivery.
Rowe fired wide of the near post from 20-yards following a well-worked free kick routine after Little was upended on the edge of the penalty area.
Assombalonga was denied by a smart stop from Martin after a clever through ball by Ajose on 17 minutes.
Alcock was the first man cautioned for a foul on the pacy Alli as MK Dons attempted to break on the counter attack. Hall saw the resulting low free-kick gathered by Olejnik.
Ajose was denied routinely by Martin before McLeod fired wide at the other end after turning on the edge of the area.
Dons appealed in vain for handball against Bostwick after a shot from Smith was charged down.
Posh created the best opportunity of the game on 57 minutes as Rowe burst into the box, but his low shot was saved by the legs of Martin and then Assombalonga somehow headed the rebound over the top.
However, moments later, Posh were in front as a low cross from Bostwick was turned home on the stretch by ASSOMBALONGA for his 26th goal of the season.
The striker had a chance to make it 2-0 moments later after holding off the attentions of Baldock but he was denied by Martin. However, as the ball ran loose, Washington was tugged back in the box by Kay and ASSOMBALONGA coolly converted from the spot for his 27th goal of the season.
Washington was then denied by Martin after racing on to a flick from Rowe before Nugent was booked for kicking the ball away.
Ajose saw a curler go over the crossbar after a quick counter attack from the boys in blue, led by a rampaging Mark Little.
New loan signing Lloyd Isgrove replaced the excellent Washington on 87 minutes as Darren Ferguson made his first change of the afternoon.
Lewington saw a left-foot drive from distance deflected inches past the post while Olejnik produced a fine stop to deny the same player as he burst into the box.
Final Score: Milton Keynes Dons 0-2 Posh
MK Dons: Martin, Baldock, Lewington, Kay, Spence, Gleeson, Smith (sub Chadwick 61min), Alli, Odelusi (sub Bowditch 61min), Hall (sub Rasulo 77min), McLeod. Unused subs: Burns, Flanagan, Randall.
Posh: Olejnik, Little, Baldwin, Nugent, Rowe, McQuoid, Alcock, Bostwick, Ajose, Assombalonga, Washington (sub Isgrove 86min). Unused subs: Day, Payne, Newell, Knight-Percival, McCann, Brisley.
Attendance: 9,526 (1,867 Posh fans)