His 4-5-1 formation reflected the realisation that a point would be a good return on a day when he was forced to do what Sven-Goran Eriksson wasn't, play a reserve side.
Despite the set-backs, it was the home team that started the brighter, and less than a minute had passed when Christophe Kinet lashed a shot inches over.
Centre-back Darren Ward almost turned in a Paul Robinson header across goal, and Republic of Ireland international Steven Reid totally missed his kick from only six yards out.
But gradually on a cold afternoon, the visitors warmed to their task.
Steve Sidwell brought a smart stop from Tony Warner, and the keeper bettered that with a breathtaking one-handed stop to keep out Steve Brown's free-kick.
The course of the game was decided in a 22nd period just before the break, as Millwall's Charlie Hearn, in behind the Reading defence, failed to pick out a team-mate with his cross. As the visitors raced upfield, Nicky Forster was on hand to steer home Andy Hughes' centre.
After the re-start, substitute Kevin Braniff's flick forced Marcus Hahnemann into action, but even then the Lions second string looked unlikely to find a way back.
Warner denied both John Salako and Forster, while James Harper struck the crossbar.
But there was little the keeper could do to stop substitute Darius Henderson's 83rd minute drive that sealed victory, ending Millwall's nine-game unbeaten run at The Den.