SCOTTSDALE, Ariz. -- The D-backs open the Cactus League season on Friday afternoon against the Rockies at Salt River Fields, as the competition for spots on the Opening Day roster will also commence.
The recent moves by the D-backs to add outfielders Jarrod Dyson and Steven Souza Jr. have solidified much of the position-player portion of the roster, and with the starting rotation set, the competition for pitchers will take place for a final few spots in the bullpen.
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With 59 players in camp, there's always a chance for a dark-horse candidate to emerge. Here's a look at two for the D-backs.
John Ryan Murphy
Murphy is more of an underdog than a dark horse for the catching competition, given that he is a well-established candidate.
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With the D-backs likely to carry three catchers again in 2018, Jeff Mathis and free-agent acquisition Alex Avila are locks. That leaves Murphy competing with Chris Herrmann for the final spot.
Herrmann would seem to have the advantage, given the fact that he has spent the past two seasons in the big leagues and is versatile enough to play all three outfield positions and the infield corners. But Murphy is probably a little ahead of Herrmann defensively, and the D-backs have noticed early in camp that Murphy worked on his swing during the offseason.
Murphy would also be a cheaper alternative, as Herrmann is set to make $1.3 million this year and Murphy would be closer to the minimum of $545,000.

Neftali Feliz
The D-backs had success last year signing veteran relievers to Minor League deals and inviting them to camp. Tom Wilhelmsen, Jorge De La Rosa and J.J. Hoover made the Opening Day roster, while T.J. McFarland also pitched significant innings during the season.
Given that history, it would not be surprising to see at least one non-roster reliever make this year's team.
Feliz could end up being one of them. The 29-year-old was a star for the Rangers as a closer when they made the World Series in 2010 and '11, before Tommy John surgery sidetracked his career.
Feliz impressed in 2016, when he compiled a 3.52 ERA in 62 games for the Pirates, and he still has electric stuff.
Because he was signed late in the offseason, Feliz missed the first few days of camp, but he impressed the D-backs' staff by the physical condition he reported in.