Rovers were behind 18-4 until four second-half tries saved the day, sealing a perfect Easter weekend following Good Friday’s derby win and allowing Smith a moment to savour his milestone.
“I’m not really into celebrating milestones but it’s not a bad way to mark my 500th game,” said a jubilant Smith, who has also coached Leeds Rhinos and Huddersfield Giants, Warrington Wolves and England.
“The players showed great character, even though they were clearly fatigued from what was a very tough derby against Hull.
“But they overcame that and they believed in themselves, maybe even more than I did.
“It wasn’t a high-quality game but that isn’t down to the players, or Toulouse, it’s simply down to the scheduling of fixtures.”
Toulouse led 12-4 at the break, Ryan Hall with the Robins’ try and extended it to 16-4 through Paul Marcon, before Hall got his second, improved by Will Dagger.
Five minutes later, George King barged his way between the posts for a simple try and Jordan Abdull then collected a fumble on the wing by Marcon and scooted inside to score.
Matt Scorton’s converted try won it for Robins before Marcon replied with a score converted by Chris Hankinson, who like Dagger kicked four goals.
Toulouse: Ashall-Bott, Marcon, Hankinson, Vaivai, Bergal, Gigot, Albert, Puech, Dixon, Stefani, Sangare, Marion, Navarrete. Replacements: Pelissier, Springer, Garbutt, Hansen.
Hull K R: Dagger, Ryan, Crooks, Kenny-Dowall, Hall, Milnes, Abdull, Storton, Litten, King, Hadley, Wood, Minchella. Replacements: Parcell, Sims, Keinhorst, Richards.
Referee: Aaron Moore (RFL).