Boston Red Sox add reliever Erik Miller, designate Ryan Watson

The Red Sox acquired left‑handed reliever Erik Miller from the San Francisco Giants in a deadline trade that sent outfielder Marcelo Mayer to San Francisco. Miller, a 28‑year‑old former Giants pitcher, made his Boston debut the day after the trade, recording a strikeout on four pitches in his sole at‑bat.

To clear a roster spot for Miller, Boston designated Rule 5 pick Ryan Watson for assignment. Watson, a right‑hander who posted a 4.53 ERA in 55 2/3 innings this season, will be placed on waivers. If unclaimed, he must be offered back to the Giants for $50,000; otherwise a claiming team must keep him on its major‑league roster for the remainder of the year.