The 22-year-old may have performed well against Gloucester last Saturday, but it mattered not as the Cherry and Whites snatched a 35-30 win with a second-half comeback.
Saints had surged into a 27-14 lead, delivering a totally dominant display during the first 51 minutes of the match.
But after Tom Collins had scored one of the tries of the season so far, the tide started to turn.
Gloucester introduced their replacements, and two of them, Louis Rees-Zammit and Alex Craig, got on the scoresheet to help the hosts snatch the victory at Kingsholm.
It was more late heartache for a Saints side who are becoming used to it.
They were also hit by late shows from Sale Sharks and Exeter Chiefs in the weeks that preceded the Gloucester game.
And having now suffered four defeats in a row, three of which have been utterly agonising, Saints have slipped down to eighth in the Gallagher Premiership standings.
Players, coaches and supporters continue to search for answers as to games have got away in recent weeks.
And there is no doubting how much of an impact the results have had on Coles and Co.
"It was pretty painful to be honest," Coles said.
"I had a couple of sleepless nights running the game back through my head.
"There's a lot to say in terms of the technical aspects of the game that let us down at the end, but the overriding theme is that we have to get these games over the line.
"It's been a bit of a theme in the past three games that we've been really in the game and playing well in large patches but then big moments let us down.
"We give away cheap tries but the opposition make us work really hard for ours. We're not making them work hard enough for their tries and that's got to be put right.
"It's really frustrating."
When asked what the mood in the dressing room has been like after the late losses, Coles added: "After the game, it's very much everyone trying to get their own head round it.
"Boydy (Saints boss Chris Boyd) will speak to us as a team and he tells us that we need to get together.
"You don't solve issues by infighting and going at each other.
"We need to have honest conversations and everyone has had to be accountable for the mistakes that were made.
"But we also need to get together as a group and find solutions.
"The supporters are rightly feeling angry about how it's going, and we feel exactly the same.
"We've just got to promise them that we'll do better and get some smiles back on faces, hopefully at the Gardens."
Coles has started each of the past two games in the six shirt, moving from his more typical role of lock.
And he said: "I'm enjoying it.
"I want as many strings to my bow as possible and hopefully it means I'm more likely to get selected because the coaches feel I can cover both positions.
"I feel like I can play there (at six) well, it's just about getting used to it.
"Often we find our back rowers are more on the width and the second rowers are more through the middle of the pitch so it's about trying to get used to that transition.
"Defence is a bit different because it's more straight down the channel, making a few more reads and you've got faster players with steps to deal with.
"But for me, I'm really enjoying the transition and it means the legs are a bit fresher from the scrums and stuff."
Coles has made 20 appearances this season, seven of which have been starts.
"It's been a bit in and out for me, I've been coming in off the bench, but now I'm getting the chance to start," he said.
"Obviously the results haven't been going as well as I wanted them to.
"I love the club, I love playing at the Gardens, so every time I put on the jersey it's great.
"Hopefully I can turn the outcomes of those games for the better."
And that all starts with Sunday's clash with Wasps as Saints aim to win at the Gardens for the first time since early December.
"One of the things we always talk about as a club is that Franklin's Gardens needs to be a fortress and you look back at the glories of this club and it was a horrible place to come and play," Academy product Coles said.
"The fans were always very loud and supportive of the team and it was really difficult to come here so that's what we want to get back to again.
"We want to right the wrongs of the last few weeks at home.
"Wasps will be a dangerous team with a very strong back row with good breakdown threats.
"Their back three is dangerous as well.
"We have to stay alive and we know that on our day we can do a job on them.
"But we've had a couple of iffy results against them in the past so we'll have to really focus this weekend.
"The energy won't be a problem - I can promise you that.
"The boys are ready to fly in and we won't be held back in that sense.
"We've just got to make sure we're accurate alongside that."