"I was nervous, but I definitely got it down,'' Coles said after the game.
"But you never know with those TMOs so I'm just glad he made the right call and made the right decision.
"I thought the ball hit the chalk, but the call's been made and I'll have a `T' next to my name.''
Chiefs coach Dave Rennie answered "nah'' when asked if he saw the ball grounded by Coles when watching the replays.
"I don't know. I had as many looks as everyone else and it looked like [the TMO] had about 15 cracks at it. But he made a decision and in the end, whether I thought it was a try or not probably doesn't matter. But the point is we shouldn't have put ourselves in that situation so we've only got ourselves to blame.''
Coles had spent the final quarter of the game filling in at the back of the scrum after the home side lost loose forwards Jack Lam and Brad Shields through injury during the bruising affair.
The last-gasp victory breathed life in to the Hurricanes' season and could prove costly for the Chiefs.
The Waikato-based outfit were after a bonus-point victory to sew up top spot on the Super Rugby ladder and lock up home advantage for the duration of the playoffs.
They now hold a two-point lead over South African outfit the Stormers who host the woeful Rebels in Cape Town on Sunday morning. (NZT).
If the Stormers claim two points from the game they will top the standings and leave the Chiefs in second place heading in to the post-season.
The Hurricanes' chances of having another game next week rely on what happens to the Crusaders, Reds, Sharks and Bulls this weekend.
Currently they hold fourth place on 57 competition points, but all four of those sides could leapfrog the Hurricanes if they were to win.
The game itself was an entertaining affair that - aside from a dull patch in the middle of the second spell - offered plenty for spectators.
Chiefs halfback Tawera Kerr-Barlow dotted down in the opening five minutes, which set the tone for the rest of the game as both sides threw the ball around in search of four tries.
Big Hurricanes prop Ben May spent time in the sin bin during the first half for an alleged tip tackle on Chiefs midfielder Sonny Bill Williams, which took away the home side's momentum.
Hurricanes wing Julian Saves bagged a double for the home side, while Ben Tameifuna and Aaron Cruden also scored for the Chiefs.
In the end, neither team could claim the bonus-point victory they desired but Coles' try, his third of the season, could be the most important one he has registered in his 47-game Super Rugby career.
Hurricanes 28 (Julian Savea 2, Dane Coles tries, Beauden Barrett 2 cons, 3 pens) Chiefs 25 (Tawera Kerr-Barlow, Ben Tameifuna, Aaron Cruden tries, Cruden 2 cons, 2 pens) HT: 18-15
