Hastings has established himself in the Warriors number 10 jersey and is likely to start in Saturday’s Guinness PRO14 final against Leinster at Celtic Park.
The 22-year-old is also in Scotland’s provisional World Cup squad and he feels Rennie’s backing has been crucial.
“When your head coach says things like that and backs you, it’s extremely pleasing,” he said.
“That’s the best thing about Dave, he backs every single one of us, and he’s not afraid to throw boys in. He put Tom Gordon straight in for his first start against Edinburgh recently and he did brilliantly.
“At the start of the season I hadn’t played too much rugby so I was maybe lacking a bit of confidence. So when the coaches are backing you, it spurs you on.”
Hastings has shown he can live with expectation after following in father Gavin’s footsteps and representing his country.
“I have kind of had that with my dad I suppose,” he said. “I have kind of been in the shadow most of my life so it’s not too big of a worry.”
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