DENVER -- The Rockies placed four players on their 40-man roster Wednesday, including their No. 8 prospect, per MLB Pipeline: left-handed relief pitcher Ben Bowden, a second-round pick out of Vanderbilt in 2016 and one of the organization’s most coveted players.

Wednesday was the deadline for protecting players from exposure in next month’s Rule 5 Draft. In addition to Bowden, the Rockies also added corner infielder Tyler Nevin (No. 11 prospect); right-handed pitcher Ashton Goudeau, who earned notice with a big 2019 with the Rockies’ system; and right-handed pitcher Antonio Santos, a hard thrower who reached Double-A in '19 and would have been coveted in the Rule 5 Draft.

The moves gave the Rockies a full 40-man roster.

Bowden, 25, made his first appearance in Minor League camp last season as a non-roster invitee in what was a get-your-feet-wet experience. This time, Bowden has a shot to swim in the deep waters.

After striking out 79 in 51 2/3 combined innings at Double-A Hartford and Triple-A Albuquerque, Bowden is a realistic contender for a big league bullpen spot. The current Major League roster has three lefty relievers: Jake McGee, James Pazos and Phillip Diehl.

“I’m always competing, and I am absolutely going into Spring Training with my head down, looking to get a job with the big leagues,” Bowden said. “If it doesn’t happen, that’s the business. You learn from your mistakes. You get right back on the horse and try to get back up there. If it does happen, you’ve got to work really hard to stay up. You’ve got to work either way.”

Bowden, a Lynn, Mass., native who helped Vanderbilt to two College World Series trips in three seasons, promptly struck out 29 in 23 2/3 innings at Class A Asheville after signing in '16. But a torn hamstring, followed by a left shoulder strain and then a back injury that required surgery, kept him off the mound in 2017.

During a solid 2018, when he struck out 78 in 52 innings over 49 appearances at Asheville and Class A Advanced Lancaster, other clubs thought enough of him to inquire about him in trade talks. Hoping to trim payroll by building the bullpen from within, the Rockies resisted.

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Bowden started 2019 at Double-A Hartford, where he posted a 1.05 ERA with a perfect 20-for-20 save conversion in 26 total appearances, racking up 42 strikeouts in 25 2/3 innings. He also earned an invite to the SiriusXM Futures Game during All-Star Weekend. Bowden advanced to Triple-A Albuquerque of the hitter-friendly Pacific Coast League, where he was 1-3 with a 5.88 ERA and one save in 22 games. He fanned 37 batters in 26 innings, but he also walked 17.

The biggest development in 2019 was the return of his fastball. Velocity rebounded gradually in 2018, but by the end of '19, it was popping at 94-97 mph. Add to that a changeup that became a weapon against right-handed hitters and a slider that has potential, but is a work in progress in terms of break and late movement, and Bowden could make a mark.

“The velo is enough to get people out," he said. "It’s just having the secondary pitches to complement it."

Nevin, 22, son of Yankees third-base coach Phil Nevin, was taken in Competitive Balance Round A in 2015 and battled injuries early in his career. But in ’19, he played in a career-high 130 games at Hartford and put up a .251/.345/.399 slash line with 13 home runs and 61 RBIs.

Goudeau, 27, was a 27th-round Draft pick by the Royals in 2012 who found his fastball-curveball mix in '19. He went 3-3 with a 2.07 ERA in 16 starts at Hartford, then forced the Rockies to protect him by going 1-0 with no runs allowed on four hits in the Arizona Fall League, matching 18 strikeouts to no walks in 13 innings.

Santos, 23, struck out 140 against 28 walks in 145 2/3 innings while posting a 4.53 ERA in 26 combined starts with Lancaster and Hartford. He also put up a 2.77 ERA in eight Arizona Fall League starts.