Berahino caused a stir in midweek when he suggested he was looking to move away from West Brom at the end of the season, and he started on the bench for the 2-2 draw at Burnley on Sunday.
Pulis insisted that Berahino's comments were nothing to do with that decision, instead citing upcoming fixtures with Swansea City and West Ham, and in any event the forward was called into action inside 20 minutes to replace the injured Victor Anichebe.
Having fallen 2-0 down to goals from Ashley Barnes and Danny Ings, West Brom fought back with headers from Chris Brunt and Brown Ideye to take a point away from Turf Moor.
"Saido came on and showed a great attitude and great appetite for it and he's a top player," Pulis said.
"The problem is he lost his father at a young age and he's not had many mentors in his life and people who can put him on the straight and narrow.
"That happens a lot today with young kids, they're not bad people they just get misguided information and advice and that's unfortunate for him.
"And it's not just Saido, that goes right through. Football is a wonderful game but there's a lot of money floating around as well and these kids can provide a lot of money for a lot of people and they need guidance.
"Bringing [Darren] Fletcher in, I'm hoping that will make a difference to Saido as well."
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