He wasn't lousy. You're frustrated at the offense. If Kremer got through 5 with 2 runs given up and the Orioles still scored 0 runs, you'd be blaming it on Kremer being lousy, Roy.
If not for the missed call Kremer is probably not out of the game after 4 and the O's would have been batting down 2-0. Diaz completely changed this game missing a ball right down the middle.