Millwall U23s remain fourth in the Professional Development League South after going down 2-0 to Queens Park Rangers at Calmont Road.
Goals in either half from Aramide Oteh and Ody Alfa (pen) secured the points for the West Londoners, who remain without defeat since September.
An even and cagy opening to the game saw most of the ball in the midfield areas, with Alfa striking wide for QPR with a low driven effort 19 minutes in.
The visitors edged onto the front foot and shortly after found themselves ahead, when Oteh received the ball from the left-hand side and rolled an accurate effort beyond David Martin off the upright.
The Lions soaked up the remaining pressure during the first half with relative ease, going in at the break with the slender deficit.
The second half saw the game predictably gradually open up, with Oteh forcing Martin into a fine stop down to his left-hand side, and Tom Elliott's header kept out by Marcin Brzozowski. Martin was again called into action to parry clear Alfa's strike.
Millwall's best chance of the match arrived 12 minutes from time, with Harry Donovan firing a cross-shot towards goal which ricocheted out to Rob Harvey - the winger putting his effort over the crossbar.
QPR saw that The Lions were made to pay as the game edged to a close, Alfa getting to the byline before being brought down by Dan McNamara. The midfielder dusted himself down to tuck the penalty into the bottom-left corner, sending Martin the wrong way.
Kevin Nugent's youngsters will look to bounce back after the turn of the year, visiting Essex to take on Colchester United on 7th January.
Millwall: Martin; Brown, Debrah, M. Wallace, McNamara; Harvey, Karacan, Donovan, Saunders-Henry (Hanson 90'); White (S. O'Brien 71'), Elliott (Wicks 64'). Subs not used: Sandford, Parker.