Yea, that is the weak spot in their roster they have not fully resolved. They traded for Burnes in the off-season and Eflin from TB in late July, but they suffered some injuries and did not have many other options.
He threw 75 pitches in 4 innings, allowed 4 hits, 1 run, struck out 3, walked 1. They lost because their offense scored one run in two games, but there are reasons for that, namely KC's pitching.