Thomas was delighted with his team’s performance as they held out against a stubborn Dalziel side and the former North Berwick head coach praised the Motherwell outfit for an improved performance at Neilson Park.
The Reds were comfortable winners when the two sides met earlier in the season but this time around it was much tougher.
However, tries from Charlie Hamilton, Kyle Hamilton and Garry Cockburn, along with 10 points from the boot of stand-off Gareth Pritchard, saw them home in miserable conditions on Saturday.
Thomas said post-match: “It’s an excellent result for us and we’re delighted to get another four points and continue our recent good form.
“I thought our pack were excellent and really matched the physicality of a big Dalziel side in what was a really tough match.
Thomas was full of praise for the visitors.
He added: “Dalziel have improved a great deal from earlier in the season, so it was great for us to get the win and we’re looking forward to East Kilbride this weekend.”
Thomas brought in Harry Hamilton for Ben Laing, who dropped to the bench, while Michael Dunlop made his debut at prop in place of Alan Laidlaw.
The Reds started brightly with their pack controlling the game early on and they were rewarded when, after a well-worked lineout and several phases close to the Dalziel line, lock Hamilton crashed over.
In difficult kicking conditions, Pritchard landed the extras to put the hosts 7-0 ahead.
The visitors kept in touch throughout and struck back shortly after Hamilton’s opening try.
The conversion, and a subsequent penalty, meant the sides were level 10-all at the break, with Pritchard having kicked a penalty for the hosts.
Haddington took the lead again early in the second half when good work by the backs put ex-North Berwick centre Kyle Hamilton away to score.
Pritchard’s conversion was off-target, but the hosts held the lead once more.
And prop Cockburn (pictured, against Dumfries) crossed after more good work by the home pack, the former skipper diving over with 15 minutes to play and allowing the Reds a quarter of an hour to push for the try bonus point.
Instead, though, the visitors hit back with their second try, and another penalty reduced the deficit further.
Dalziel left Neilson Park with a losing bonus point after landing a third penalty of the match with the game’s last play.

Haddington: James Ferguson, Kyle Adams, Kyle Hamilton, Liam Clutton, Ian Watt; Gareth Pritchard, Jack Hamilton; Michael Dunlop, Colin Stuart CAPTAIN, Garry Cockburn, Harry Hamilton, Charlie Hamilton, Kyle McGarvie, Kris Paterson, Mark Renton.
Replacements: Alex Cunningham, Jonny Riddell, Ben Laing and Mark Robertson