Kimbrel will join the Cubs ahead of Thursday's series finale against the Braves, Sahadev Sharma of The Athletic reports.
Kimbrel is ready to make his long-awaited 2019 big-league debut after completing his fourth appearance with Triple-A Iowa on Tuesday, striking out two across a perfect ninth inning. It's unclear if Kimbrel will immediately take over closer duties, but he should get there soon enough.