Bafetimbi Gomis scored a double as Lyon moved top of Ligue 1 with a 4-1 home win against promoted Troyes on Saturday as champions Montpellier fell to a shock 2-1 defeat at Lorient. Montpellier had led until the dying minutes after Emanuel Herrera’s 37th-minute opener but late strikes from Alain Traore and Jeremy Aliadiere gave the Brittany outfit their first win of the season. Earlier Lyon kept their unbeaten record and their cool despite temperatures reaching 37 degrees celsius and losing midfielder Yoann Gourcuff to a right knee injury after just six minutes. The French international, who has had a promising start to the season after a 2011-12 blighted by injury, is suffering from suspected ligament damage.