Alex Brandon / AP

Nationals third base coach Bo Porter interview today to become the 2013 manager for the Houston Astros, a person with knowledge of the meeting confirmed. first reported Porter’s involvement.

Porter, in his second season with the Nationals, lives in the Houston area. Last year, the Nationals interviewed him before bringing back Manager Davey Johnson. He also interviewed with the Nationals in 2009 before they decided to retain then-interim manager Jim Riggleman.

Last fall, Porter also interviewed to become the Marlins’ manager before they hired Ozzie Guillen. He has also previously interviewed for a managerial position with the Pirates.

Porter is regarded as a potential eventual successor to Johnson. When Johnson steps aside, the Nationals want to replace him with an in-house candidate. Other possibilities include bench coach Randy Knorr, first base coach Trent Jewett and Class AAA Manager Tony Beasley.

Along with his third base coaching duties, Porter coaches outfielders and coordinates the Nationals’ base running.

The Astros fired Brad Mills last month and replaced him with Tony DeFrancesco on an interim basis. Coming off a 106-loss season, the Astros again have the worst record in baseball at 45-98.