Red Sox fans will get their first look at half of the return from the Brandon Workman/Heath Hembree trade from last month on Tuesday night, as Nick Pivetta is coming up to make his major-league debut. The righty has been down in Pawtucket since the trade and will now have time to make a couple of starts — the team has announced he’ll start the season finale on Sunday — before the end of the year. In order to make room for Pivetta, the team sent Robert Stock down to Pawtucket.