Marcus Semien is not in the lineup Thursday against the Cubs.

Semien is not in the lineup Thursday against the Cubs.

Analysis:

Semien will sit for the second time in four games, as Conor Gillaspie takes over at third base and bats second against right-hander Jake Arrieta. A fixture in the lineup in April, Semien has gotten off to a 3-for-18 start to May and could be in danger of losing out on regular playing time.