Steve Cotterill endured a miserable return to Portsmouth as his Nottingham Forest side were beaten 3-0 in the npower Championship.
Cotterill left Pompey in mid-October after 16 turbulent months in charge to succeed Steve McClaren at the City Ground.
But Erik Huseklapp pounced to put Pompey ahead against the run of play on the stroke of half-time, Dave Kitson (76) made it two and Huseklapp's second six minutes from time confirmed Cotterill's misery.
Leaders Southampton surrendered a two-goal lead but rallied to win 4-2 at Coventry.
Richard Chaplow netted for the Saints in the 34th minute and Adam Lallana doubled the lead five minutes later, but Lukas Jutkiewicz got the hosts back into it two minutes into the second period.
Clive Platt's opportunistic strike in the 70th minute pulled the hosts level, but seven minutes later Guly Do Prado put Southampton back into the lead and Steve de Ridder rounded off the scoring five minute from time.
Second-placed West Ham were comfortable 2-0 winners at Hull.
Sam Baldock opened the scoring for the Hammers from close range four minutes after the break and Jack Collison made it 2-0 eight minutes later.