The biggest match in French football takes centre stage on Sunday evening at the Parc des Princes, with both sides needing wins to offset respective crises.Paris Saint-Germain coach Carlo Ancelotti has various injury worries to mull over ahead of his first major test as trainer of the nouveau-riche capital club - the visit of bitter rivals Marseille where victory could see them top the Ligue 1 table should leaders Montpellier suffer defeat.Clement Chantome is out with a hip injury, with Diego Lugano, Alex and Thiago Motta all rated as doubtful for Sunday\'s match for various reasons. In their absence will be Milan Bisevac, who deputised for Alex in last weekend\'s 2-1 defeat to Nancy, as well as Blaise Matuidi, who continues his run in the first team.Jeremy Menez is also rated 50-50 to participate in the crunch clash, with Ancelotti forced to either revert to a 4-3-1-2 with Christophe Jallet moving to the right-hand side of midfield and Ceara slotting in at right-back. Moreover, Kevin Gameiro could fill in Menez\'s role, supporting Guillaume Hoarau up front.Nene\'s public outburst in being dropped last weekend amid discontent in the dressing room has seen him offer an apology, and he should feature, with Mamadou Sakho and Maxwell returning to the side as PSG seek a first league win in four games.Olympique de Marseille, meanwhile, have problems of their own. Confidence is down at the Provence club after a record 10 games without a win, with reports surfacing of a rift concerning certain players\' workrate, which has seen the 2010 champions plummet to ninth place.Souleymane Diawara is out for the season following knee surgery, with Rod Fanni set to move into central defence as cover. Alou Diarra was suspended for Wednesday\'s 2-0 Champions League quarter-final defeat to Bayern Munich and returns to the starting XI. Loic Remy was taken off shortly after half-time at the Allianz Arena, but is thought to have overcome his hamstring problem.Sunday\'s Clasico will have a bearing on where the Ligue 1 title ends up in May, with L\'OM hosting leaders Montpellier in another crunch game on Wednesday.