The hooker took full advantage of Ross Ford’s injury to turn out a man-of-the-match performance with two tries — but saw the hosts concede five times in an 11-try thriller at Murrayfield.
Scotland were not at their best all afternoon and looked as though they could have been heading for an embarrassing defeat after the Pacific Islanders clawed their way back from 32-10 down.
McInally, earning his first cap for over a year, admitted there was plenty of work to be done before the visit of New Zealand next week.
“It was 32-10 when I went off, with a bit of breathing space,” he said. “But it was a concern how quickly they responded to our tries.
“In a way we’re disappointed, but in a way it’s probably better than it going perfectly at the beginning.
“Ahead of next week we have a lot to work on, we’ll look at our defence and in particular our defence in our 22; they seemed to score a wee bit too easily so we’re happy, but there’s a lot to improve upon.”
He added: “It was frustrating that whenever we had the ball and [were] holding onto it, we were either scoring or getting a penalty, and likewise whenever Samoa had it, it was the same story.”