NASHVILLE - There is little need for an elite-level closer on a rebuilding team. That philosophy led the Phillies on Wednesday night to trade Ken Giles to the Houston Astros.

According to MLB.com, the Phillies traded Giles for Brett Oberholtzer; Vincent Velasquez; a minor leaguer, Derek Fisher; and a player to be named. The deal is pending physicals.

The rebuilding Phillies will likely lose more often than they win next season, which makes a player such as Giles expendable. They were able to flip a closer for multiple young pitchers. First-year general manager Matt Klentak has repeatedly said that he wants to "augment" the team's pitching depth.

The Phillies will now have to find a reliable closer - just like Giles - in time for when their rebuilding project yields winning results. One of those options could be minor-league righthanders Edubray Ramos or Jimmy Cordero.

Velasquez, a righthander, matches a mid-80s slider with a mid-90s fastball. The 23-year-old reached the majors in June, finishing his rookie season with a 4.37 ERA in 552/3 innings. He broke in as a starter but was shuffled to the bullpen after seven starts when the Astros acquired Scott Kazmir. Houston drafted him in the second round in 2010. Velasquez missed all of 2011 after undergoing Tommy John surgery. He spent most of his time in the minors as a starter, which is what the Phillies likely consider him to be.

Oberholtzer, a Delaware native, started 42 games over the last three seasons. He had a 4.46 ERA in eight starts last season. The 26-year-old lefthander struck out 27 batters and walked 17 in 381/3 innings. He spent the season's final two months in triple A.

Fisher is an outfield prospect from Western Pennsylvania.

Giles became the Phillies closer in July, when the team traded Jonathan Papelbon to Washington. His first save came in Toronto and the final out was a fly ball to the warning track. Giles, 25, finished the season with 15 saves. He struck out 87 batters and walked 25 in 70 innings. His blazing fastball and intense demeanor made him a perfect fit for the stress of the ninth inning.

"Once he got past that original performance, he knew he 'was the guy.' For that role, you've got to have that kind of mentality," manager Pete Mackanin said.

Giles' replacement with the Phillies may have been acquired on Wednesday morning. The Phillies made their first move of the winter meetings by signing righthander David Hernandez to a one-year contract. The deal, according to Yahoo Sports, is worth $3.9 million and includes incentives based on how many games Hernandez finishes.

The 30-year-old returned last June after missing all of 2014 because of Tommy John surgery. Hernandez, who spent his last four seasons with Arizona, finished the year with a 4.28 ERA in 332/3 innings. Most of his outings were in the seventh inning or later.

Hernandez seemed to improve toward the end of the year, and his elbow became further removed from surgery. He allowed three earned runs in his final 101/3 innings. The pitcher recorded scoreless appearances in 10 of his final 12 games.

"Throughout the last couple of months, we've been adding a lot of depth to our bullpen. Many of those players don't come with a lot of experience," Klentak said. "So we wanted to make sure that we added at least one player who added a lot of experience who could help to pitch in the late part of the game. David, during his time in Arizona, was one of the better setup men in baseball."

It is unclear whether Giles will assume the closer's role in Houston. The Astros signed Luke Gregerson last December to a three-year contract. The 31-year-old righthander converted 31 of his 36 save chances last season. He struck out 59 batters and walked 10 in 61 innings.

No matter how they split the duties, the Astros should have a formidable late-inning pair with Giles and Gregerson. Giles may not be closing games, but it is certain he will get the chance to showcase his ability in meaningful situations.

The Trade

Astros receive

Ken Giles (age 25)

2015: 6-3, 1.80 ERA, 15 SVs, 87 SOs, 25 BBs

Phillies receive

Vincent Velasquez (age 23)

2015: 1-1, 4.37 ERA, 58 SOs, 21 BBs

Brett Oberholtzer (age 26)

2015: 2-2, 4.46 ERA, 27 SOs, 17 BBs

Derek Fisher (age 21)

2015 (High A): .262 BA, .471 SLG, 16 HRs, 63 RBIs, 23 SBs

A player to be named