The Rebels last season overcame a 24-point deficit to beat the Highlanders 38-37 at AAMI Park but there was no repeat on Friday night.
Coach Tony McGahan lamented their inability to clear the ball from their 22 with their woeful kicking game putting unwanted pressure on the side.
"We fought really well all night on both sides of the ball but unfortunately every time we scored points we were unable to exit our bottom end and that put us under pressure and they were able to get points pretty easily," McGahan said
"It's a big one for use to lose and we need to make sure our nines, 10s and 15s are controlling that part of the field."
He said that Hegarty had recovered well but concussion protocol would dictate whether he would be available for their clash with the champion Chiefs next round.
Despite the win, halfback Smith was in no mood to celebrate his 50th game for the Highlanders.
"It was an awesome night but I'm gutted, I gave them two tries and I'm pretty gutted about that.
"We were humming along and just silly mistakes, missed tackle and an intercept, wrecked my night," he told Fairfax.
"We got the win in the end and I'm just very happy the boys showed some spirit in that last 10 minutes."
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