Villanueva has been told that he will make the 25-man roster out of camp, MLB.com's Jenifer Langosch reports. While Villanueva's career as a starter fizzled out, he has complied a 3.55 ERA and 439 strikeouts in 439 career innings as a reliever. He should slot in as the Cardinals' long reliever, pitching mostly in low-leverage situations.

Villanueva signed with the Cardinals on Wednesday on a deal that includes an invite to spring training, Derrick Goold of the St. Louis Post-Dispatch reports. Villanueva started five games for the Cubs in 2014, but made most of his appearances out of the bullpen and finished the season with a 4.64 ERA and 1.39 WHIP with 72 strikeouts over 77.2 innings. He will likely battle for a bullpen slot out of spring training, with the ability to be a spot starter for the Cardinals if needed.

Villanueva continued his strong second half with 1.2 innings in Friday's game that was not officially completed until Saturday. Though his year-to-date numbers do not reflect it, Villanueva has pitched well since the break, compiling a 1.57 ERA and 24:4 K:BB ratio in 23 innings. He was a disaster as a starter this year (10.53 ERA in five starts), but in 35 appearances as a reliever, he has a 2.65 ERA and 1.16 WHIP. He does not look like a big-league starter anymore, even though he keeps getting opportunities.

Villanueva picked up his second save of the year on Tuesday. He pitched a scoreless 12th inning while striking out two to down the Rockies. Rondon blew the save in the 11th, which set things up for Villanueva to get his opportunity in the 12th. Villanueva gave up a one out hit, but worked around it with a strikeout and a ground out to end things. While he didn't work out as a starter, Villanueva has excelled in the bullpen, posting a 2.70 ERA and a 39:13 K:BB over 40 innings.

Carlos Villanueva will start for the Cubs on Saturday against the Nationals in Washington. Jeff Samardzija had been the scheduled starter, but was traded to the Athletics late on Friday. The veteran right-hander owns a 5.91 ERA and 1.64 WHIP over 45 2/3 innings on the season, and is likely to be on a limited pitch count on Saturday. He should be avoided in all fantasy formats.

Carlos Villanueva will be moved to the bullpen. The Cubs will activate Jake Arrieta (shoulder) from the disabled list to start Wednesday against the Reds, so Villanueva will be bumped to the pen. It's not a big surprise, as the 30-year-old has a rough 10.42 ERA and 2.21 WHIP across 19 innings this year.

Carlos Villanueva struggled again in Friday's loss to the Brewers, surrendering five runs on 11 hits over his five frames. He walked one and struck out one during the difficult outing. The Brewers jumped on him with a pair of runs in the first inning, then tacked on single runs in the third, fourth and fifth to complete the damage. Villanueva simply hasn't been good enough while holding down a rotation spot for the injured Jake Arrieta, compiling a 10.42 ERA and 2.21 WHIP over 19 innings. If he gets another turn through the rotation, it would come against the Reds in Cincinnati on Wednesday.

Carlos Villanueva was hit hard again Sunday, giving up five runs on nine hits over 4 2/3 innings in a loss to the Reds. Villanueva did punch out seven in the outing, but it's a shallow silver lining for an otherwise ugly showing. It leaves the right-hander with a 10.93 ERA and 2.14 WHIP for the year. With Jake Arrieta nearing a return -- possibly as soon as this weekend -- Villanueva's time in the rotation is short.

Carlos Villanueva was rocked for nine runs over three innings in Saturday's loss to the Cardinals. Villanueva gave up 10 hits (including a home run), so nearly half of the 21 batters he faced managed to reach base. The 30-year-old has now allowed 12 runs on 20 hits in just 9 1/3 innings of work this season. Look for him to move back to the bullpen when Jake Arrieta (shoulder) comes off the disabled list. That should happen pretty soon.

Carlos Villanueva could be scratched from Sunday's scheduled start against the Phillies after appearing in relief on Monday and Wednesday. Villanueva took the loss in both extra-innings games versus the Pirates. Because he only threw a total of 30 pitches in the two appearances, it's still possible he'll start Sunday. If the Cubs decide against it, they could call someone like Chris Rusin up.