PITTSBURGH -- The Angels have scratched Nick Tropeano from his scheduled Saturday start at PNC Park because of an undisclosed ailment. The team said it will provide additional information after Tropeano undergoes further evaluation.Jhoulys Chacin will take Tropeano's place, starting on normal rest thanks to a scheduled day off on

PITTSBURGH -- The Angels have scratched Nick Tropeano from his scheduled Saturday start at PNC Park because of an undisclosed ailment. The team said it will provide additional information after Tropeano undergoes further evaluation.

Jhoulys Chacin will take Tropeano's place, starting on normal rest thanks to a scheduled day off on Thursday. The Angels were still unsure whether Tropeano would require a stint on the 15-day disabled list as of late Friday night, moments after their 9-2 win over the Pirates in the series opener.

Tropeano's spot in the rotation would come up again on Tuesday.

Aside from Tropeano, the Angels have four injured starters, including Garrett Richards , Andrew Heaney , C.J. Wilson and Tyler Skaggs. The injury toll on their rotation previously prompted them to sign Tim Lincecum and acquire Chacin via trade.

Tropeano has given up two earned runs or fewer in seven of his 10 starts this season.