And it looked like being another disappointing outing for the hosts when, at 27-20 down, Toulon captain Bastareaud was dismissed.
The France centre could have few complaints after his reckless forearm made contact with the head of a prone Castres player.
Hot-headed Bastareaud sees red!
— Sky Sports Rugby (@SkySportsRugby) September 9, 2018
But Louis Carbonel reduced the deficit with a penalty five minutes from time before Filipo Nikosi touched down to salvage the win for a Toulon side who have looked a long way from their former glory in the early part of the season.
The result lifts Toulon to 11th, while Castres sit fifth after three matches.
In the day’s early kick-off, Pau won 24-21 to leave struggling Grenoble without a victory so far this season.
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