MILAN, April 5 (Reuters) - Daniele De Rossi's penalty 10 minutes from time helped AS Roma beat Genoa 3-2 on Saturday to move within one point of Serie A leaders Inter Milan. Champions Inter can re-establish their four-point advantage at Atalanta on Sunday but will be without injured top scorer Zlatan Ibrahimovic. Genoa forward Marco Borriello needlessly brought down Rodrigo Taddei and Rossi blasted the ball home to spare second-placed Roma's blushes after throwing away a two-goal lead. AC Milan also cut the gap on fourth-placed Fiorentina to a point after Filippo Inzaghi and Kaka returned from injury to score in a 3-1 home win over struggling Cagliari. Kaka burst forward and unleashed a superb shot to give Milan an early lead before Inzaghi glanced home Andrea Pirlo's 31st-minute corner thanks to more charitable defending. The Sardinians were given hope when Zeljko Kalac, in good form since replacing Dida as Milan's number one, allowed Daniele Conti's free kick to roll in under his body before Inzaghi netted his second in the 69th minute. Carlo Ancelotti's side, who lost 2-1 at home to Atalanta last weekend, go above Udinese into fifth with Cagliari remaining third from bottom. Fiorentina host lowly Reggina on Sunday. DIPPING SHOT In Rome, the hosts opened the scoring on 14 minutes when Taddei tapped in a rebound after goalkeeper Rubinho had blocked his first effort from Max Tonetto's cross. Striker Mirko Vucinic, standing in for the injured Francesco Totti, doubled the lead four minutes later with an excellent dipping shot from 20 metres. Genoa then scored twice in a minute in the second half, Marco Rossi netting after Borriello's shot was saved and forward Julio Cesar Leon equalising with a fierce effort. Inter's lead was 11 points in mid-February but Roma have whittled that down to a point for the first time and have six games left to try to snatch their first championship since 2001. 'We believed even when we were eight points behind. They have difficult fixtures, however so do we,' De Rossi said. The win was a boost for Roma ahead of Wednesday's Champions League quarter-final second leg at Manchester United where the Italians must overhaul a 2-0 deficit. Totti is battling to recover from a thigh problem in time for the game.