Dumbarton lost 2-1 after two second-half goals from Motherwell gave the visitors the victory at the Cheaper Insurance Direct Stadium.

The Sons initially took the lead through a spectacular overhead kick from Robert Thomson, but second-half goals from Ross Maclean and Craig Moore gave The Steelmen the win.

Spectators had to be briefly evacuated from the stands midway through the second half after the fire alarm was set off by one of the stewards.

But the home fans will be worried about Gregor Buchanan, who went off injured after 60 minutes.

Dumbarton's defence is already looking thin before the season has even begun after captain Darren Barr had been ruled out earlier this week with a nerve injury in his back.

There were numerous chances for both sides early on, with Buchanan header forcing a goal line save from Dean Brill and Motherwell fired two shots off the post in quick succession shortly after.

But it was Thomson who acrobatically gave the Sons the lead, slotting home an overhead kick after 23 minutes and his second during Dumbarton’s pre-season.

The ball rolled out to David Smith from a Dumbarton corner, and the former Brechin City striker was ready and waiting, spectacularly firing in from the edge of the six-yard box to give Dumbarton the lead.

But the Premiership team reminded them how dangerous they were on the break, with Frazer Wright brilliantly turning a cross from Lionel Ainsworth behind, denying Maclean a tap-in at the back post a few minutes before half-time.

Motherwell had more possession in the first half but were unable to find the final pass, and often being guilty of overplaying on several occasions.

The Sons made several subs after the break, bringing on goalkeeper Jamie Ewings and trialist Josh Todd – a midfielder who played for Annan last year to replace Frazer Wright.

Well came straight out of the blocks, dominating the early stages of the second half and finally got the breakthrough from Maclean after 60 minutes.

Substitute Moore initially had his effort bounce off the crossbar, but the ball fell to Maclean who was there ready for the easy finish.

Buchanan, who had taken a few knocks today, was subbed off shortly after and walked straight down the tunnel. – Aitken confirmed after the game it looked like concussion for the defender.

Dumbarton began to apply pressure, looking to restore their lead but it was the visitors who snatched the winner.

Confusion between Craig Pettigrew and replacement keeper Ewings resulted in both players going for the ball, and this allowed Moore to walk the ball into the net.

And there was brief interruption in play after a fire alarm went off in the stadium, with the crowd having to be evacuated from the stands.

Dumbarton pushed for an equaliser but Motherwell were able to hold out.

The Sons next game is away to Forfar in the League Cup next Saturday, kick-off 3pm.

Team Sheets:

Dumbarton:

Brown (Ewings 46), Pettigrew, Docherty, Buchanan (Clark 61) Fleming, Thomson, Smith, Wright (Todd - Trialist 46), Stirling. (McCallum 73)

Substitutes: Ewings, Todd - Trialist, McCallum, Clark.

Motherwell:

Brill, McMillan, Chalmers, Ferguson, Kennedy, Campbell, Ainsworth, McHugh, Moult, Thomas, Maclean.

Substitutes: Peter Morrison, Trialist, Heneghan, Moore, Watt, Mackin, Hastie, Trialist, Trialist.

Referee: W Collum

Assistant Refs: C Hilland, C Phillips