IT is, of course, more than a little ridiculous to suggest Alan Stubbs needed to win this game, but it’s also accurate.

After three matches without a victory from 90 minutes – they did win all three penalty shoot-outs – there were more than a few grumblings from St Mirren supporters, even now, worried their promotion-winning team had lost more than just a manager.

Stubbs has made wholesale changes, too many his critics complain, and the fear among some Buddies was this new team would take too long to gel for what is a major step-up.

Even a convincing win over Dumbarton, now a League One club, is hardly a landmark but the fact they have reached the last 16 and scored some good goals here was welcome.

“I am hopeful of being busy, I am hopeful of getting a striker in this week but I was hopeful a few weeks ago," said Stubbs about transfers.

"We are trying. You could think you are going down a blind alley and then within one phone call you could be close to signing three or four. This is the crazy time of the season when you think you have something and then you don't.

"However, I was pleased the players got a win in front of the home fans. We looked a bit sharper and then to find out we had gone through was a real boost."

St Mirren’s Hayden Coulson was in a hurry and scored his first for the club two minutes into the match when he picked up a loose ball, drove past three Dumbarton players on his way into the box and then produced a cool finish.

The second was lovely. With ten minutes of the half to go, Danny Mullen’s pass found Paul McGinn. His cross from the right was superb, as was Cammy Smith’s header which he put back across the keeper.

It was 3-0 not long into the second half when a slick passing move ended with another McGinn cross. This time picking out Ross Stewart whose header was never being kept out.

The fourth, scored on 53 minutes by captain Stephen McGinn, was a belter. Picking up the ball a good 30 yards out, he sent his shot into the top corner. A fifth came along on when Jim Kellerman scrambled home the loose ball from a corner which should have been cleared.

And number six was taken with six minutes to go when the excellent Smith lobbed Grant Adam from 40 yards. It was a terrific piece of skill.

Stevie Aitken, the Dumbarton manager, admitted it was not his team’s best day.

He said: "That was embarrassing. It's not acceptable and I told the players that but I take responsibility because I pick the team.

"I have worked with a lot of the same people for a long time but we have 12 new players in and they will need to get up to speed. I expect my team to compete and we were second best all over the park.

"I've learned a lot about the players in terms of us going forward."