The Red Sox bullpen situation this season in two words: not ideal.
This is the same problem that persisted last season, only it is worse now without Craig Kimbrel (Joe Kelly was a liability in the second half, so yeah, that's not really part of the problem). However, the team could (eventually) be bailed out by some younger help and the ship might not sink after all.
Most notably, Marcus Walden has shined in the 'pen--and that's wonderful. The 30-year-old, who averages around 94-95 with his fastball, has shown himself to be a solid option; the former starter has whiffed 15 batters in 11.1 innings over eight outings while posting a 2.38 ERA. As MassLive points out, he could be this year's Ryan Brasier.
The team's miserable day night doubleheader against the Detroit Tigers also provided some further clues. Travis Lakins and Darwinzon Hernandez made their MLB debuts to bail out the predictably short relief outing Hector Velazquez gave the team. Hernandez, the Red Sox top pitching prospect, offered up 97 MPH from the left side; he might be a AA starter, but he could help the big league team later in the season.
And Lakins, who replaced Poyner on the roster, could be an upgrade over someone in the back end (Colten Brewer or Tyler Thornburg); after all, he has a 2.21 ERA in 16 AAA relief outings dating back to last season. Not to mention, he has pretty solid command.
Austin Maddox (0.53 ERA in 17 big league outings in 2017), Carson Smith (2.66 ERA in 29 outings with the Red Sox) and Zach Putnam (3.20 ERA in 145 MLB games) are all currently on the DL for the PawSox. If any of them get healthy, those could be some viable bullpen options for the team.
Not to mention former TCU closer and 2018 third round draft pick Durbin Feltman (44 Ks in 29.1 pro innings) is already in AA, so he might be on the big league fast track.
Hang tight, bullpen. Help may come... eventually.