Britain's Kerr outsprints Hocker for world indoor 3,000m gold
Kerr hit the front at the bell and clocked 7min 35.56sec for victory in a tactical race, 0.14sec ahead of US rival Cole Hocker.
France's Yann Schrub claimed bronze.
"It's nice to be back to where I was," said Kerr, who won the world indoor title two years ago but sustained a calf tear at last year's 1,500m final at the world outdoors in Tokyo.
"This race didn't go the way I wanted it to go, but racing is all about dealing with the situations you are put in.
"I shouldn't worry much about the mistakes in the race, although there were a lot of them today. I didn't have time to think about them, I had to push.
"I wanted this gold medal so badly. I had all kind of scenarios in my head and I am just pleased it all went in my favour today."
The 15-lap race had been heralded as one of the stand-out events at the world indoors.
The 15-strong field featured the full men's 1,500m podium from the 2024 Olympics along with the world 3,000m steeplechase champion, New Zealand's Geordie Beamish, in a stacked clash of medallists.
Hocker, who already has Olympic 1,500m and world 5,000m titles to his name, was targeting his first world indoor title after 1,500m silver in 2024, while 2023 world 1,500m champion Kerr was eyeing a second world indoor title two years on from his victory in Glasgow.
Also in the running was the USA's Olympic 1,500m bronze medallist Yared Nuguse, who got 3,000m silver behind Kerr two years ago.
Tactical race
Luan Munnik took up the early running, the South African closely followed by Hocker, who soon took over the lead, with Nuguse on his tail.
Kerr ambled along in the middle of the pack as the Ethiopian pair of Addisu Yihune and Getnet Wale surged with nine laps to go.
Beamish was in last, well off the pace, which saw the field split into single file through the halfway mark.
Kerr made his way up through the field to sit on Hocker’s shoulder in fifth.
With two laps to go, it was still the Ethiopians in control, but their teamwork went astray as they collided.
It was then that Kerr made his move past Hocker and Nuguse.
As the bell rang for the final lap, Kerr struck, Schrub following on his coattails.
Hocker kicked down the home stretch to nip in front of the Frenchman, but he had left himself too much to do and Kerr streaked through with gritted teeth for a second world indoor title.
"I have won at world outdoors and world indoors back to back and I took it for granted," said Kerr.
"I thought I would be at the top of the sport for a long time but, after missing a couple of opportunities that I wanted, I am really going to enjoy this gold.
"It took a lot of work to be standing on the podium today."
Hocker said it was "a bit of a disappointment not to come away with the gold".
"Getting a medal is always incredible and I am proud of it but you've got to shoot for the stars."
Nuguse finished fifth behind Kenya's Jacob Krop, while Beamish eventually came in 14th, almost 10sec down on Kerr's pace.