London Irish director of rugby Brian Smith was full of praise for Shane Geraghty after he kicked a last-gasp drop goal to send Exeter down to a fourth consecutive defeat.
Exeter looked in control at the interval but they had a disastrous third quarter and fell away to another hugely disappointing 28-26 loss.
Blair Cowan scored two of the Irish tries, Tom Guest and Alex Lewington the others, while Geraghty kicked a conversion and dropped the decisive goal, with Tom Homer adding a penalty.
"Most sides would have played for a penalty and we made the correct decision but very few ball players would want to step up like that and it shows the class of the man," Smith said of Geraghty.
"I thought we had blown our chance, when we gave away those two penalties in quick succession and I knew (Gareth) Steenson wasn't going to miss.
"Losing down there was the turning point of our season. They celebrated hard; it didn't go unnoticed and it hurt us, so there was plenty of motivation today."
Exeter managed only two tries through Dean Mumm and Dave Ewers in the match, with fly-half Gareth Steenson kicking four penalties and two conversions.
Geraghty hailed Tomas O'Leary's perfect pass in the run up to the winning kick.
He said: "Missing earlier penalty kicks was not in my mind but it all happened so quickly.
"I thought the game was gone but I wanted the drop kick chance early as I didn't want to go through eighteen phases. It was a great pass from Tomas O'Leary as it was timed to perfection."
Exeter boss Rob Baxter accepts that his side are going through a difficult period.
"The next win is proving tough to find," he said.
"We are a little bit hesitant and we are expecting things to happen as opposed to making them happen."
"Having been on a losing run, we knew it was going to be a bit nervy and despite what I said, it was. We had an opportunity to move up to fourth place but we didn't take it."
Despite the disappointing loss, Baxter praised his side's efforts for coming back into the game after a disastrous third quarter, which saw them go for 13-5 ahead to being 22-13 behind.
"We bounced back from two scores and it would have been very easy to cave in. With a minute to go we were up and in control of the ball in their 22 but it wasn't to be," he added.
Exeter now have a break from the four week break from the Premiership to undertake LV= Cup and European Challenge Cup fixtures which Baxter viewed as beneficial.
He said: "It will make a difference as it will give us a bit of a distraction from our run in the Premiership. We'll look at this performance in the week ahead and deal with it with a bit of brutal honesty."