SCOTTSDALE, Ariz. -- Left-hander Jorge De La Rosa is back where he likes to be -- in the D-backs' clubhouse competing for a role on the roster.
When De La Rosa made the team in 2017, he was something of an underdog. It was his first attempt at regular relief work since he left the Brewers in 2006. Since then, he pitched a year-and-a-half in Kansas City then anchored the Rockies' rotation, where he is still the organization's winningest pitcher with 86 wins and nine scattered relief appearances.
The veteran, who will be 37 in April, faces similar odds in breaking into a crowded D-backs' bullpen competition in 2018, but he relishes the chance to prove himself yet again, having signed a Minor League contract just as camp was opening for pitchers and catchers.
"I try to compete every year," De La Rosa said before his workout Monday. "I just do my job and make them make a decision. I enjoy every time I pitch."
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De La Rosa was 3-1 with a 4.21 ERA last season, throwing 51 1/3 innings in 65 appearances while striking out 45 and allowing just one earned run in his last 13 games, spanning 7 1/3 innings. Facing a higher percentage of lefties than he did in his career as a starter, he held lefties to a .194 batting average.
Manager Torey Lovullo likes what he's seen so far from De La Rosa, noting that the veteran is showing the club what they got used to last year.
"He attacks hitters, whether it's a left-handed hitter or a right-handed hitter," Lovullo said after De La Rosa faced the White Sox Sunday. "The heartbeat is fantastic. He doesn't get glossy-eyed in any situation. I handed him the ball in a role that we want him to go out and execute in, and he got a big strikeout. He did that all year last year."
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There are two other prominent lefties competing for bullpen roles, Andrew Chafin and T.J. McFarland. Chafin pitched in 71 games for the D-backs in 2017, posting a 3.51 ERA and striking out 61 in 51 1/3 innings. McFarland appeared in 43 games over 54 innings, posting a 5.33 ERA while striking out 29.
De La Rosa takes nothing for granted and is focusing on improving one of his secondary pitches as he works through the spring.
"I'm trying to work more on my slider this year," he said. "I'm trying to throw it a little different than last year, and that's working so far. I keep practicing and throwing it a lot."

After five Cactus League appearances, De La Rosa is starting to find his rhythm, notching his eighth strikeout Sunday against a total of two walks in 3 2/3 innings.
A key question in determining De La Rosa's chances of making the roster is the number of lefties Lovullo plans to keep come Opening Day.
"Perfect balance would be at least two," Lovullo said. "In game planning against teams that have at least two lefties in the bullpen, it can be very challenging to come up with a strategy to get the best matchup possible. I would prefer at least two, but we haven't figured out that final number."
De La Rosa knows he needs more than just a familiar arm to make the cut. He needs to show his arm can continue living up to the expectations he set last year. His own newfound familiarity with the relief role is helping him prepare and produce the results the D-backs need to see.
"Last year at this time it was a little tough for me getting ready, but this year is easier," De La Rosa said. "I'm just trying to stay healthy. I know I can pitch every day, so I try to get ready every day."