Bath started their Champions Cup campaign with an emphatic win over Munster last weekend, while three-time champions Toulon were looking to bounce back after a poor defeat in Edinburgh.
Van Graan brought in 20-year-old Vilikesa Sela to replace injured England prop Will Stuart as Bath went toe to toe with Toulon’s imposing pack.
Finn Russell’s penalty kick gave Bath the lead but second row forward Brian Alainu’uese muscled over from a line-out move to put the hosts ahead.
Both sides traded penalties before Ted Hill burrowed between two defenders from a tap penalty to briefly give Bath the lead.
After Mateo Garcia’s penalty levelled the scores at 13-13, three-time European champions Toulon regained the lead. Former Harlequins prop Kyle Sinckler powered towards the posts before being hauled down, Toulon moved the ball wide and Juan Ignacio Brex strolled over.
Toulon thought they had scored again in the final action of the first half, but Bath held the ball up to keep the deficit to five points.
Garcia kicked another penalty as the hosts started to dominate up front in the second half but Bath dug deep to keep in touch.
Scrum-half Tom Carr-Smith, making his first European start in place of captain Ben Spencer, was involved as Santiago Carreras dived over for the visitors’ second try.
Russell’s conversion closed the gap to one point but back came Toulon. Sinckler again played a prominent role with a surging run and Toulon worked the ball to the rapid Drean, who restored the home side’s eight-point cushion.
Bath turned to their bench and replacement Arthur Green grounded the ball from close range to cut the deficit.
But Ludlam buried over for Toulon’s bonus-point try from a five-metre scrum, and Garcia’s steely conversion from the touchline extended their lead to eight points once again.
Hennessey’s try showed Bath’s resilience but a Toulon maul proved to be unstoppable as the hosts sealed victory.
