A person with knowledge of the negotiations says Baker is working to finalize an agreement to become manager of the Houston Astros. The 70-year-old Baker becomes the oldest manager in the big leagues. He takes over from AJ Hinch, who was fired Jan. 13 just an hour after he was suspended for the season by Major League Baseball for his role in Houston’s sign-stealing scandal.  The hiring of Baker is a sign the Astros want to bring an old-school mentality and stern presence to a franchise reeling from the dismissal of Hinch and general manager Jeff Luhnow.