Jim Goodwin paid tribute to his players for never throwing in the towel at Rugby Park.
The Buddies twice found themselves behind as relegation-threatened Kilmarnock battled hard to save their Premiership skins.
But St Mirren weren't to be denied and they fought their way back to bag a point after a breathless end to their 3-3 draw which saw three goals scored in the final 15 minutes.
Goodwin was proud of his squad for showing such resilience, especially having suffered Scottish Cup heartache just three days earlier.
He told Express Sport: "For a neutral, it was an entertaining game but there is plenty to work on defensively for both managers.
"On a positive side, we showed great character to come back from being behind twice.
"We were flat in the first half but we showed great fight to come back from 2-0 down.
"Cammy MacPherson's goal was the best of the night and it's probably our goal of the season.
"It was a great team move and a great strike to cap it off.
"I think a draw was fair, although Tommy will be disappointed."
The Saints manager was delighted with substitute MacPherson's performance in particular, with the youngster reacting in the perfect way to missing out on the club's Scottish Cup semi-final tie.
Goodwin added: "It was a great goal and fantastic individual strike from MacPherson.
"At half-time, if you'd offered me a point considering how poorly we'd been playing, I'd probably have snapped your hand off.
"When it went two each I'd say we were in the ascendency and probably thought we'd go on and win it.
"It was a fantastic save by Alnwick in the end to earn us the point."
Goodwin's side now have a chance to finish in seventh spot in the Premiership, if they bag a win over Dundee United in their final game of the season on Sunday and Motherwell fail to win at home against Ross County.