SEATTLE -- The positive news from the Mariners’ clubhouse on Sunday morning was that Marco Gonzales was playing catch ahead of Sunday’s 2-0 win over the Angels. The uncertainty was that Seattle doesn’t yet know who will pitch in place of its No. 1 starter on Monday even after the matinee that clinched its fifth series win.

Gonzales went on the 10-day injured list on Thursday after an MRI revealed a left forearm strain. That blow followed an impressive start he made in Houston on Tuesday. But now his turn in the rotation is up again, and the Mariners -- who lost James Paxton for the season and are without Paxton’s replacement, Nick Margevicius -- find themselves in a quandary for innings allocation.

They may have hinted at their solution by recalling right-hander Erik Swanson from the alternate training site. He took the spot of Casey Sadler, who was placed in the 10-day IL with right shoulder inflammation. Swanson pitched two hitless innings in Baltimore during a doubleheader on April 13, and he is a former starter, though it’s unclear how stretched out he’ll be. Robert Dugger could also be considered, Mariners manager Scott Servais said. Dugger threw 51 pitches in Saturday’s 10-5 loss.

Regardless, the Mariners are headed toward a bullpen day for the first round of replacing Gonzales -- but it’s unclear if they’ll stay that way. They do benefit from two off-days in a five-day span beginning Thursday.

“We're going to have to lean on our bullpen. … With those off-days coming up, I'm very hopeful that Marco is not out that long -- maybe just a couple starts missing him,” Servais said. “But we'll have to wait and see how that comes along.”

Seattle’s bullpen was dominant in April, compiling a 2.35 ERA and holding opponents to a .552 OPS -- the second and best marks in baseball, respectively. But it also only pitched 95 2/3 innings, which were the 14th-most in that span.

That workload figures to increase in May, particularly if the Mariners stick with a six-man rotation, which Servais reiterated on Sunday that they are. They also haven’t discussed the possibility of piggybacking a bulk-innings pitcher, such as Ljay Newsome and Dugger, with an opener, a tactic they used a handful of times in 2019.

“The reason that you would use an opener is maybe you like that matchup against the top of their lineup in the first inning. That's the reason behind an opener,” Servais said. It's not just to fire [a] guy out there, and he's going to throw an inning, and then you could have another guy behind him throw an inning, and another guy behind him thrown inning or two. That's not really the purpose of an opener, in my mind.”

Nottingham dealt back to Brewers
Catcher Jacob Nottingham’s Mariners tenure came to a close after just four days. Nottingham was dealt back to Milwaukee for cash considerations on Sunday, and he was in the Brewers’ lineup against the Dodgers at Miller Park, and to boot, he crushed two homers. Nottingham was acquired from Milwaukee to be a depth bat with Evan White going on the bereavement list on Friday, and though he didn’t appear in a game with Seattle, he did leave an imprint.

J.P. Crawford, who knew Nottingham during their amateur days in California, used one of Nottingham’s bats on Saturday en route to a 2-for-3 night with an RBI double. But with his abbreviated teammate now gone, he’s already ordered a new set.