After missing the fairway well right and hitting his approach long, Kisner lagged a putt from off the green to 5ft seemingly securing his par at the final hole.
After igniting the crowd with an up-and-down to save par on the final hole, Spieth stood on a chair near the scoring area to peer over the crowd at the 18th green.
Jamieson dropped three shots in his first three holes to fall five off the lead, but a run of six birdies in seven holes around the turn saw him surge back up the leaderboard.
"I played great today", said the 26-year-old South Korean-born Lee, whose game is back on track after a quiet six-month stretch.
For Rahm, his wonderful rookie season continues with his sixth top 10 in addition to his win at the Farmers Insurance Open.
He turned pro after college, spent three years (2007-09) on mini-tours before advancing to the Nationwide (now Web.com) Tour in 2010.
Alex Noren went into his final round of the PGA Championship hoping to play well so he could start next week on a high and came out of it with what he later reckoned was probably his best ever performance over 18 holes, a West Course record of 62 and enough to win the tournament by two strokes.
He made a giant leap forward in 2015, zooming up the world ranking on the strength of three second-place finishes - all coming in playoff losses.
On Sunday at Colonial, Kisner chose to leave nothing to chance.
"I'm bitterly disappointed at the minute", Lowry said.
After successive missed cuts and a poor start to this event, Spieth could at least take heart from his encouraging form over the weekend. Casey fired a 68 that included a curving, 23-foot birdie putt on the final hole and Lee followed in the next-to-last group with his own 16-foot birdie to finish off a 69.
It is on the second time in 12 years for the 54-hole leader at Colonial to have more than a one-stroke advantage.
Henrik Stenson was the first to falter, dropping two shots in three holes on the 13th and 15th, and despite a final-hole birdie he wasn't able to recover any more of the defecit, ending the event tied for third at eight-under-par with Nicolas Colsaerts and Hideto Tanihara.
She led by one shot after a bogey-free third round Saturday, then kept the competition at bay on the 6,734-yard course at Travis Pointe Country Club in Ann Arbor, Mich. He also just missed a 12-footer at No. 9, and a 25-footer at the 446-yard 12th hole rolled over the left edge of the cup. But in terms of pure clout, there's not a much better non-major championship victory than holding off Spieth and Rahm at a classic track like Colonial that has produced so many spectacular winners.
Simpson, the 2012 U.S. Open victor playing in the final group, started the round with birdies at the first two holes.
Olympic champion Justin Rose scored an eagle on the par five 18th to salvage his round and finish two over.
"I need to go out (on Sunday) and play well and just go and put a good score on the board".
The trio sit on 7-under-par overall, one shot ahead of German golfer Max Kieffer.