The Reds handed recalls to Alex Cunningham and Gavin Stewart following their impressive displays with the 2nd XV, while the backs were again unchanged.
The match also saw Haddington don their new strips for the first time this season. The club are continuing their relationship with Tustain Motors as main sponsor, and representatives from the company were at Neilson Park to hand over the new jerseys ahead of kick-off.
Haddington started the match the better of the two sides, with the back-three of James Ferguson, Kyle Adams and Mark Robertson threatening when the ball made its way wide.
That dominance came from good work by the forwards, where Kris Paterson and Garry Cockburn impressed, and there were industrious shifts from Charlie Hamilton and skipper Colin Stuart.
South African stand-off Gareth Pritchard was the first man to go over, and he was closely followed by countryman and number eight Kyle McGarvie.
Pritchard converted, and kicked a penalty to ensure Rhodri Thomas’ side had a good lead at the break, turning round 17-5 to the good.
Basement side Irvine, with only one win in the league this season, struggled to get into the match, but their heavy pack did pose some problems for the home side.
Irvine produced an improved second-half performance, but they were never in contention as a brace from Mark Robertson and another score from the impressive McGarvie secured victory. The Reds move up to third, and are just six points behind league leaders Dumfries Saints.
Thomas’ side are on the road on Saturday, as they take on fourth-place Perthshire.

Haddington: James Ferguson, Kyle Adams, Kyle Hamilton, Liam Clutton, Mark Robertson, Gareth Pritchard, Alex Ferguson; Colin Stuart (c), Alex Cunningham, Garry Cockburn, Ben Laing, Charlie Hamilton, Gav Stewart, Kris Paterson, Kyle McGarvie
Replacements: Rab Watt (on for Cunningham), Harry Hamilton (on for Laing), Connor Munro (on for A. Ferguson)