AC Milan gave title rival Juventus a boost as it was held to a 1-1 draw at Catania in Serie A on Saturday.
Brazilian striker Robinho put Milan ahead in the first half before Nicolas Spolli equalized in the 57th minute.
Robinho almost added a second goal when his shot appeared to have crossed the line.
Catania's Alejandro Gomez had a shot ruled out for offside. The Argentine had earlier hit the crossbar.
Defending champion Milan remains top, five points clear of Juventus which hosts Napoli on Sunday.
Milan, held to a midweek goalless draw in the Champions League against Barcelona, plays the second leg on Tuesday.
Catania attacked from the start and Gonzalo Bergessio went close in the fourth minute when he raced into the right side of the penalty area but sent his effort wide of the near post.
The visitors went close again moments later when Sergio Almiron just missed connecting with a teasing cross from Marco Motta.
Milan's first decent opportunity came in the eighth minute when Urby Emanuelson muscled his way into the area but Catania goalkeeper Juan Pablo Carrizo got down well to deflect the Dutchman's effort to safety.
Carrizo again did well in the 17th to deny Zlatan Ibrahimovic from point blank range after the Sweden striker had chested down Massimo Ambrosini's clever pass over the defense.
Bergessio went close moments later but his header scraped the top of the crossbar.
Milan took the lead in the 34th as Robinho lashed the ball into the bottom left corner after a deft one-two with Ibrahimovic.
Catania almost leveled immediately but Gomez's curling shot crashed off the crossbar.
Gomez had the ball in the back of the net less than two minutes after the break, but the Catania forward was judged to have been offside.
Catania equalized 10 minutes later when Nicola Legrottaglie headed the ball and Spolli sidefooted it home from close range. It almost went in front shortly afterwards when Almiron's fierce effort just flew over the bar.
Milan went closer to restoring its lead as Robinho rounded Carrizo before slotting the ball towards goal. Giovanni Marchese cleared off the line although the ball appeared to go over.
Ambrosini thought he had given Milan the lead in the 76th but Carrizo pulled off another brilliant save to keep out the Milan captain's header at full stretch.
Carrizo again came to his team's rescue seconds from full time to deny Ibrahimovic's strike, shortly after the striker had sent an effort whistling past the far post from a tight angle.
Catania could have snatched all three points in stoppage time as first Mariano Izco and then Francesco Lodi had shots blocked by the Milan defense.
