Right-handers Adam Ottavino (0-1, 1.72 ERA) and Edgmer Escalona (0-2, 1.96) and left-hander Josh Outman (1-0, 4.50) are practically regulars, and most of the time they're working during close games.
Rockies manager Walt Weiss is being careful with starter innings. Just twice a starter pitched seven innings -- Jon Garland in an 11-3 victor over the Mets, and Jhoulys Chacin in an 8-3 loss to the Rays on Sunday. Also, Jeff Francis and Juan Nicasio have pitched as many as six innings just one time, and in many of their games the score is still close when they're labored to the point they have to leave. That means games are in the balance when the middle relievers pitch.
"Our bullpen is designed maybe a little bit differently than most in that we want to keep those guys fairly busy and give them opportunities to get consistent innings to take some heat off the starters and the back end of the 'pen," Weiss said. "They serve a dual purpose. At the same time, those are three pretty darned good arms that you run in there. Those guys have been very valuable."
The Rockies' bullpen structure retains the best of last year's mostly panned experiment with a four-man rotation with tight pitch limits. Last year's system had three relievers who were scheduled to throw on a rotating basis, and then-manager Jim Tracy had to use them that way. This year, Weiss has more flexibility. However, Ottavino, Escalona and Outman have fallen into a pattern that has left them comfortable with their roles.
"It's an interesting role to be in because you're not really available every day necessarily because you have to be ready to throw multiple innings every time that you go in there," said Ottavino, who flourished under last year's system to the tune of a 5-1 record with a 4.56 ERA in 56 appearances. "It's not a priority to have you available every day, because they have the other [two] guys. So we kind of are like in a mini-rotation."
For example, on Wednesday at Los Angeles, Nicasio labored for 92 pitches in four innings but left with the Rockies leading, 5-3. The Dodgers faced Nicasio with a lineup heavy on left-handed hitters, which made them ripe for Outman to hold them to one hit for two scoreless innings. Outman was the winning pitcher, since Nicasio didn't meet the five-inning minimum for a starter to receive credit.
"You kind of know based on who's throwing," said Outman, who began the year at Triple-A Colorado Springs before replacing a struggling Chris Volstad on April 20. "They go on matchups. If [Jorge] De La Rosa starts, it's better to use Escalona or Ottavino with all the right-handers that are out there. With Juan starting [against the Dodgers], I had three left-handers I could deal with out there.
"They're able to set it up to play to each of our strengths. We know who's available on that night. We know what we're going to be expected to do."
Outman and Ottavino are former starters who didn't immediately find their footing with their previous teams -- Outman with the Athletics, Ottavino with the Cardinals -- but found homes by pitching multiple innings in shorter bursts.
Escalona has always worked relief, but he was at the back of the line when it came to the late innings. The Rockies trust the final innings to lefty Rex Brothers, righties Matt Belisle and Wilton Lopez, and righty closer Rafael Betancourt.
In his last five outings, Escalona has given up just one unearned run, and was tagged with a loss at Arizona on April 27. Saturday against the Rays, he replaced Garland with a 4-3 lead and allowed just one baserunner in two innings.
"For me, I feel comfortable and it helps when the manager has confidence in you," said Escalona, whose previous experience was 41 games with the Rockies from 2010-12. "They believe in me when I come to the mound. Everybody knows I can do a great job. So I'm happy, because everybody knows I can compete and get guys out."
As long as they're settling down close games -- keeping the Rockies ahead or keeping them close when they are behind -- they're doing their job.
The lone exception came Sunday, when Outman gave up two runs, one earned, and those reduced the chance of a comeback in an 8-3 loss to the Rays. Other than that and the four runs Outman gave up pitching in a game against the Braves that was out of hand, he has kept the score the same in his other outings. Since April 9, the only two runs off Ottavino came in a victory, and four of the five runs scored off Escalona have come in wins.
"We have a good idea of the order of things down there and everybody's throwing well," Ottavino said. "We're just trying to keep that going."