The Houston Astros have decided to go in a different direction with their bullpen signings after missing out on Andrew Miller and David Robertson. They've already signed a former reliever of the Oakland Athletics to a three-year deal and are looking to add another right-hander.

On Tuesday morning the Astros and right-hander Luke Gregerson agreed to a three-year, $18.5 million contract, according to Bob Nightengale of USA Today. Gregerson has spent six seasons in the MLB as a reliever with the San Diego Padres and Oakland Athletics. He's been one of the most consistent bullpen arms in the league over that span and has maintained a 2.75 ERA and 1.08 WHIP in 419 1/3 innings.

His best season came in 2014 with Oakland, during which he went 5-5 with a 2.12 ERA and 1.01 WHIP in 72 1/3 innings. Gregerson only has 19 career saves, but could serve as the Astros' closer due to their horrid bullpen woes in 2014. The team had a closer-by-committee system that didn't seem to work out too well after they led the league in blown saves (26) and had the worst ERA (4.80). Although Miller and Robertson were seemingly Houston's first choices this offseason, Gregerson will be a significant upgrade. The closer role could be up for grabs depending on how Chad Qualls performs in 2015.

The Astros are aware more work needs to be done. They're also "closing in" on former St. Louis Cardinals reliever Pat Neshek, according to Nightengale. The 33-year-old Neshek also had his best season as a reliever in 2014 after compiling a 7-2 record to go along with a 1.87 ERA, 0.79 WHIP, six saves and 68 strikeouts in 67 1/3 innings. It was his first All-Star season in the right-hander's eight-year career.

Jerry Crasnick of ESPN also mentions Neshek is in serious talks with two other clubs and a "resolution is expected soon." If the Astros can land him, they would have their seventh, eighth and ninth inning pitchers ready for 2015.

UPDATE: The Astros and Neshek have agreed to a two-year, $12.5 million contract with a third-year option, according to the St. Louis Post-Dispatch.