Johnson had a three three-run homer for his second hit of an eight-run sixth inning, leading the surging Royals to a 10-1 victory over the Rays.
"It's hard to describe the first time back," he said. "I wish everyone would get a chance to understand what it's like and it's really hard even to put into words."
Traded to Kansas City by the Rays in February, Johnson led off the big inning with a single and chased Jeremy Hellickson (4-3) with his second homer of the season, both coming off Hellickson.
Johnson got his third hit of the game in the eighth inning and is 6-for-11 with four RBIs against his former team while batting .202 with three RBIs against every other team.
"When they came into our place, I had a good series there," Johnson said. "I wasn't really playing that well, and Ned (Yost) gave me some opportunities to play against them. I picked it up and today played well again. It's good to get them anyway you can, but it feels good to get them against them, of course. (Former Rays pitcher James) Shields said the same thing; he wishes he could pitch here."
Ervin Santana (5-5) gave up five hits and an unearned run in 7 2/3 innings.
The Royals, who have won eight of nine, set a franchise record by holding an opponent to three runs or fewer in a 12th straight game.
"Everything is going our way right now so we have to keep that up," Santana said.
Hellickson lost for the first time since April 25, giving up eight runs on 10 hits in 5 2/3 innings. He retired 15 of the 16 Royals he faced in the first five innings.
"He was locating his fastball and his changeup really kept us off stride," said Kansas City bench coach Chino Cadiha, who was acting manger while Yost attended his daughter's wedding in Georgia. "I guess we figured it out in the sixth, and here we go."
Johnson led off the sixth inning of a scoreless game with his first hit. After Alcides Escobar's double, Alex Gordon drove in the first run with Kansas City's third straight hit. Three more singles and an RBI double by Miguel Tejada preceded Johnson's homer to give the Royals an 8-0 lead. In all the Royals sent 11 men to the plate in the inning.
"I just fell behind to Elliot, the first batter of the inning, and just couldn't stop it after that," Hellickson said. "I'm pretty frustrated. It wasn't a fun game. Eight runs, it's unacceptable."
It was the Royals' biggest inning of the season, exceeding the seven runs they scored in the third inning at Los Angeles on May 15.
Gordon had two hits in raising his road batting average to .381, compared to .231 at home.
Matt Joyce had two hits for the Rays, who have lost four of five.
The Rays optioned Odorizzi to Triple-A Durham after the game and took pitcher Alex Cobb off the bereavement list. ... Tampa Bay LHP David Price (strained left triceps) threw 54 pitches over three innings in a simulated game. The AL Cy Young Award winner could rejoin the rotation in late June or early July. ... Rays 3B Evan Longoria got his second break from playing on the artificial turf in five games, getting the start as the DH. Kelly Johnson made his first start this season at third in place of Longoria. ... RHP Nate Adcock, designated for assignment by the Royals on June 6, was claimed on waivers by Arizona. He was optioned to Triple-A Reno. ... Tampa Bay LHP Matt Moore (8-2) looks to stop a two-game skid, in which he allowed 15 runs, in Friday night's game with the Royals. RHP Luis Mendoza (1-3) will start for Kansas City.