"Last night, I used [starter] Jorge De La Rosa in the seventh inning, I used Matt Daley in the seventh inning and I used Franklin Morales in the seventh inning to put it down," Tracy said. "Is it out of the realm of possibilities to use another guy if I had to put an inning down? Absolutely not."
The Rockies received Beimel, 32, and $300,000 in cash considerations from the Nationals for Triple-A right-hander Ryan Mattheus, who recently underwent right elbow surgery, and Class A right-hander Robinson Fabian.
The trade comes with the Rockies entering Friday night's game against the Reds one game behind the Giants in the National League Wild Card race and third in the NL West, eight games behind the Dodgers and trailing the Giants.
The Dodgers added lefty George Sherrill from the Orioles, and the Giants acquired Pirates All-Star infielder Freddy Sanchez and Ryan Garko from the Indians. The Rockies' answer was to improve the bullpen, first with Betancourt, who came for Class A pitcher Connor Graham, and now with Beimel.
Beimel was 1-5 with a 3.40 ERA with the Nationals but was a key member of a Dodgers team last year that won the NL West. He doubles the number of lefties in the Rockies bullpen.
Beimel, who has appeared in 435 career games with the Pirates, Twins, Dodgers, Rays and Nationals, serves as a contrast to the young Morales, who was a starting-pitching prospect before he was recalled three weeks ago.
"What we have now are two left-handers in our bullpen with very interesting contrasts," Tracy said. "One [Morales] is a big-time power guy, and the other guy is a breaking-ball-type left-hander that can surprise you with a good fastball. He can throw a fastball in a very good spot.
"The thing that I really like about Joe Beimel is what he adds is experience, and he has the capability of making a very good left-handed hitter in the middle of somebody's order take a bad swing."
The Rockies have had a star-crossed season from the left side of the bullpen this year. Glendon Rusch and Randy Flores struggled and lost their roster spots. Alan Embree suffered a fractured right tibia when he was hit with a line drive on July 10 and is expected to miss the rest of the year, although he has hopes of returning.
The Rockies attempted to sign Beimel as a free agent during the winter but couldn't reach an agreement. Beimel signed a one-year, $2 million contract with the Nationals in March, well after Spring Training began.
Beimel's arrival comes late but in time for a bullpen with just one member -- Street -- who was on the Rockies' Major League roster when the regular season began. Beimel also increases the bullpen's big-game experience quotient.
"It really helps the next two months when you start really getting into the race, when you start crunching the numbers -- one game back, two games ahead, a half-game here, a half-game there," Street said. "Actually, more than anything, experienced guys who can eliminate all that and just pitch -- it's not as if they feel like the whole team is right on their shoulders."
Earlier talks with the Nationals and the Orioles, who have lefty Mark Hendrickson, didn't produce a deal because the Rockies wanted to hang onto speedy second-base prospect Eric Young Jr., who could help in a reserve role during the late-season stretch run.
Mattheus, 25, who pitched in last year's Futures Game during All-Star weekend, went 1-1 with a 4.32 ERA in 13 games covering 16 2/3 innings before undergoing season-ending surgery on July 13. He also had rehab stints at Class A Modesto and Double-A Tulsa.
Fabian, 23, went 3-6 with a 6.24 ERA in 24 games, including 12 starts, for Class A Asheville.