Toulouse maintained their four-point lead over Clermont in the French Top 14 title race on Saturday but they were forced to come back from a 14-10 half-time deficit to beat Castres 34-27. The champions, missing a host of players on Six Nations duty, ran in four tries through winger Yves Donguy, prop Census Johnston, centre Florian Fritz with a 77th-minute try from back-rower Gilian Galan sealing the points. Clermont, who beat Toulouse last weekend, saw off Agen 29-20 with tries scored by winger Brent Russell and hooker Benjamin Kayser. On Friday, Argentina international Juan-Martin Hernandez, who missed the World Cup last year and sat out seven months of action, suffered another injury setback. Hernandez, 29, came off after just 18 minutes of Racing-Metro\'s 22-13 win over Bordeaux after hurting an upper leg muscle. The Pumas star was forced to miss the World Cup in 2011 after suffering right knee ligament damage in March.