Bergman threw 7 1/3 innings of two-hit ball the previous night in a 4-0 win over Oakland.
"It's been great," manager Scott Servais said of the unexpected boost from the rotation additions. "Good for them. [Pitching coach Mel Stottlemyre Jr.] has done a good job game planning. Not trying to get too complicated and too detailed, but trusting their stuff.
"Both guys have a lot of movement on the fastball. It's not going to overpower you, but the movement, the location, mixing in pitches, and the game planning and those guys taking their stuff and running with it, it's been key not trying to do too much."
Gaviglio, who grew up as a Mariners fan in Ashland, Ore., tried to downplay making his first Major League start.
But when pressed, he acknowledged it was pretty cool getting his first chance to pitch at Safeco Field, with numerous family members making the trek from Oregon to see him. When he played at Oregon State from 2009-11, his team twice played at Safeco, but he didn't get a chance to take the mound in either game.
So, yeah, this was something special.
"It was awesome," he said. "I dreamed of playing here when I was a kid. It's a long road and once you see the process of what it takes to get to the big leagues, the chances of making it to the team you watched growing up are pretty slim. A lot of it is out of your control."
He's with the Mariners now only because injuries have sidelined four-fifths of Seattle's original rotation as Felix Hernandez, James Paxton, Hisashi Iwakuma and Drew Smyly are all on the disabled list.
But like Bergman the night before, he took advantage of his opportunity and impressed Servais in the process.
"Sam Gaviglio gave us a great effort tonight," Servais said. "I'm excited about what I saw. Really good sinker, had the breaking ball working and I thought after five innings, he gave us about all he had."
The 26-year-old became the 10th different Mariners starter this season, the most in the Majors.