Updated

The Houston Astros have named Bo Porter their next manager.

Porter is currently the third base coach for the Washington Nationals and will remain in that role through the team's run through the playoffs.

The Astros fired Brad Mills in August and replaced him on an interim basis with Tony DeFrancesco, who will remain on the job through the end of Houston's second straight disastrous season.

After a franchise-worst 56-106 record in 2011, the Astros are on their way to eclipsing that mark at 51-105 with just six games remaining. The Astros had never lost 100 games before last season.

"Bo's experience and management style will help lead our young players in creating a sense of urgency to restart the Astros' winning tradition," said owner Jim Crane.

The 40-year-old Porter played three seasons in the majors with the Cubs, Athletics and Rangers from 1999-2001 and has made his way through the coaching ranks. He was the Marlins' third base coach from 2007-09 and started 2010 as Arizona's third base coach before taking the reins as the Diamondbacks' bench coach when Kirk Gibson was promoted to manager that July.

"Bo Porter has been successful as a player and as a coach and is ready to lead the Houston Astros as our next manager," said Astros general manager Jeff Luhnow. "He is a natural leader and a winner and he inspires people around him to be their best. He is driven to succeed and we look forward to seeing the positive results as he channels his energy and expertise toward creating winning teams in Houston."

Porter, a Houston resident, was the manager of the Marlins' New York-Penn League affiliate in 2006.

The Astros started with nine candidates for the position, then trimmed the list to four finalists, including Porter and DeFrancesco.

"The finalists were all uniquely qualified to lead this team going forward," Luhnow added. "In the end, we selected the candidate that best fit the criteria we were seeking and is best suited to lead the Astros through this transition phase and help us achieve our common objective of consistent competitiveness and ultimately, multiple championships."

In addition to the managerial change, the Astros will also switch leagues next year. The club played in the National League from its inception as an expansion franchise in 1962 and will move to the American League next year as part of the realignment that will give each league 15 teams.