Jarvis (0-2) was the losing pitcher in Saturday's 5-4 extra-innings loss to Baltimore. He allowed one run on one hit and two walks while striking out one over one-plus innings.
Nelson came away with a no-decision in Saturday's 5-4 extra-innings loss to the Orioles, giving up three runs on 10 hits over 4.2 innings. He struck out three without walking a batter.
Pfaadt (1-3) took the loss Friday as the Diamondbacks fell 4-2 to the Orioles, giving up three runs on five hits and two walks over six innings. He failed to strike out a batter.
Arizona manager Torey Lovullo said Friday that Thomas (hamstring) will seek a second and third opinion on his MRI results, Steve Gilbert of MLB.com reports.
Thompson allowed one hit and permitted two inherited runners to score over a scoreless third of an inning Thursday, getting charged with a blown save in a 5-4 win over the Reds.
Cecconi did not factor into the decision Thursday against the Reds, allowing one run on three hits and three walks over 5.1 innings. He struck out two.
Rodriguez is close to being able to begin a throwing program after an MRI on Wednesday showed healing in his left shoulder, Nick Piecoro of The Arizona Republic reports.
Montgomery (2-2) picked up the win Wednesday, allowing two runs on seven hits and two walks over seven innings in a 4-3 victory over the Reds. He struck out two.