Based on Jennings' situation, Kiermaier will be with the team at least through Sunday's series finale against the Angels. He understands his situation is short term, but that didn't seem to bother him.
"I'm just pumped to be back up here with the guys," he said.
Earlier this season, the 24-year-old Kiermaier served a two-game stint with the Rays when the team played a weekend series in Cincinnati. Highly regarded for his defensive abilities, Kiermaier made his mark in the Rays' 1-0 win over the Reds on April 12.
The rookie center fielder charged a single through the middle and threw a strike to catcher Ryan Hanigan, who was waiting at home to apply the tag to Joey Votto. After the game, Rays manager Joe Maddon noted: "That's the play of the game, that's the play of the season so far."
Kiermaier was optioned back to Durham after that game and he's continued to progress offensively. He is hitting .322 with three home runs and 10 RBIs with 10 stolen bases and an OPS of .855 for the Bulls.
"Ever since my callup to Cincinnati, they told me to keep ironing things out offensively," Kiermaier said. "I took that to heart and I said, 'Man, I've got to make the adjustments to get back up here.' And I've felt really good the past two or three weeks down there in Durham. I'm really happy where I'm going in my progression offensively."
Rays fans also remember Kiermaier for joining the Rays' roster for Game 163 at Texas last season,and he also appeared in the Wild Card Game at Cleveland.
Kiermaier posted his first Major League hit in the sixth inning Saturday, beating out an infield single.
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.