The 27-year-old netted in the second half just moments after teeing up Djeidi Gassama, while he also had a hand in the fifth goal of the day when Ross McCausland fired home from a tight angle.
Speaking to RangersTV after the victory, a delighted Penrice said: “It was a dream debut. With the mental week that I’ve had, it was a great debut to top it off.
“It’s been a crazy week. It was on and off, on and off, then finally I got it confirmed to get the flight back and get the medical done.
“My goal? I thought there was a good chance the ball would drop to that side because there was no-one in there.
“I just ran in, and thankfully I wasn’t offside. I was a bit nervous when they were drawing the lines and the referee had his hand to his ear, but thankfully it’s counted, and I’m just delighted.”
It was a first victory of McInnes’ tenure, and a much-needed triumph to give everyone a lift ahead of Thursday evening’s UEFA Europa Conference League qualifier at Ibrox.
The full-back only took part in his first training session yesterday, but he admits he has been impressed by the quality inside the dressing room.
Penrice added: “I’ve watched every single game and it’s been coming.
“It’s just that bit of confidence, and you could see when they scored that wee dipped a wee bit.
“But that’s football, and you’re not going to play an unbelievable 90 minutes every week.
“It’s something to build on; it’s not finished just yet, but it’s definitely a start.
“Going into the game, it was all about just getting through. But I think we’ve added a performance to that as well; a really emphatic win, which is a positive too.
“The dressing room is littered with talent. It’s about getting that out of the boys.
“I knew a couple of the boys before I came in, and it’s a talented building.”
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