Jamieson leads from Hovland in Abu Dhabi as McIlroy stutters
There were struggles, though, for the tournament's two biggest names as four-time major champion Rory McIlroy had to settle for an even-par 72, while world number two Collin Morikawa carded a disappointing 73.
On a low-scoring day, world number 336 Jamieson rolled in nine birdies in a bogey-free effort.
The 38-year-old is looking for a first win on the DP World Tour, formerly known as the European Tour, since 2012.
"I kept telling myself that you have to hit the ground running here because it could ultimately dictate how your season goes," said Jamieson, playing his first event since November.
"If you miss the first two cuts of the year, then all of a sudden you feel like you're miles behind because there's such a great prize for the first couple of events."
Hovland, who is Europe's top-ranked player after two straight wins late last year, made birdies on three of the last four holes to be Jamieson's closest challenger.
The 24-year-old stumbled with a bogey on the 12th after a rapid start, but poured in a 30-foot birdie putt on the 15th to spark himself back into life.
"That was nice, I didn't hit the best of shots early, but I was able to get away with it," said the world number seven, who struggled with jet lag earlier this week.
"I holed a bunch of putts today and that certainly woke me up from the jet lag."
Former Ryder Cup player Thomas Pieters of Belgium is third on seven-under, while Ian Poulter and Tyrrell Hatton are in a five-way tie for fourth, one stroke further back.
McIlroy, a four-time runner-up in the tournament, has work to do just to make the cut after an up-and-down day.
The Northern Irishman rebounded from a sloppy front nine with back-to-back birdies on 13 and 14, but saw his good work undone when his second shot to the par-five closing hole found the water.
Reigning British Open champion Morikawa, who also won the season-long Race to Dubai last season, made an unhappy return to the United Arab Emirates.
The American managed just two birdies and made a bogey and a double-bogey as he slipped immediately to 10 shots off the pace.