Archer, new to Dubbo in 2019, has been one of the competition's best so far this season but before Saturday he had yet to enjoy a win in the Blowes Clothing Cup.

Archer was away for the Roos' win over Orange City in April so it was a sweet feeling when the full-time siren sounded at No. 1 Oval on Saturday and a 27-20 victory over Forbes was confirmed.

"First win with the Roos and it's a lot of fun," Archer said after a string of close-fought losses.

"It's taken a while but the boys have worked hard and it's paid off for us. It's good to get this win."

A bumper Old Boys' Day crowd had little to cheer about in the first half as a catalogue of Roos errors and penalties left players and fans alike frustrated.

The hosts dominated proceedings in the first 40 but had little to show for it as the Platypi went into the break with a 10-7 lead.

But a try shortly after the restart for Ned Williams got the hosts rolling and while it still wasn't perfect, things began to click.

The Platypi showed signs of fatigue after a huge defensive effort in the first half and the Roos forward pack soon took control.

Mark Baldwin seemed to be everywhere and was a pillar of strength for the hosts, while tries to inspirational forward leaders Shaun McHugh and Archer sent the Roos on the way to victory.

"We have the ability to smash teams but we're just our own worst enemy," Archer lamented.

"I don't think it was as close physically, it was more just about our discipline."

The huge amount of defensive work done in the first was was pleasing for Forbes captain-coach Jack Hammond but he confessed it took a toll late on.

"We defended well and think that was half of it. We we pretty tired after defending all the first half and we'd been defending well and held them off when they were throwing everything at us," he said.

"That was the difference, we were a bit more tired in the second half and they held on to the ball and got across the line."

It was the Platypi who got across the line first in the round seven match, marching downfield off the back of a penalty and scoring through Hammond's co-captain-coach Jarrod Hall.

Angus King converted that and nailed a penalty 10 minutes later to set up a 10-0 lead, but any more attacking raids from the Platypi in the first half were few and far between.

The Roos set up camp in the opposition half and a mountain of possession made it seem like tries were inevitable but a stack of handling errors - namely from Williams and Tim Beach - and ill-discipline saw chance after chance go begging.

Scrumhalf Hamish Gordon eventually took matters into his own hands and darted forward from the back of the ruck and muscled his way across to ensure the Roos only trailed by three at the break.

The sides traded tries early in the second stanza - Williams' try cancelled out by a slick five-pointer for Platypi fullback Josh Coulthurst - before tempters began to fray.

After plenty of niggling and chat during the match, things went close to boiling over when some push and shove broke out but after a stern talk from referee Pete Thomas both sides got back to playing rugby.

And it was the Roos who were playing the better, and they soon got back in front courtesy of a strong close-range effort from McHugh, and after Gordon slotted a penalty shortly after it was Archer's five-pointer nine minutes from team which secured the result.

The Platypi scored on full-time through Tom Macleay, but it was mere consolation as the Roos finally managed to hold things together late on after a number of close losses.

"Even though they scored we're starting to learn to play 80 minutes," Archer said.

"That feeling in the last 10 or 15 there, we could have let it go but we held it this time."