Both drafted by the Mariners, Paxton signed in 2011, and Zunino in '12. They've been up and down since and most recently spent the beginning of the season in Triple-A Tacoma, both working out the kinks before being recalled. Paxton came up on June 1, and Zunino got the call Thursday after Steve Clevenger fractured his hand Wednesday.
Zunino made his season debut Saturday night, hitting a pair of home runs, including a two-run shot in his first at-bat. He also threw out Orioles shortstop Manny Machado attempting to steal second base.
"We've been working together for a long time and kind of learning together," said Paxton, who earned his second win. "He knows me really well and knows what I'm working on, knows what I'm capable of. So it's just nice to have a guy back there to know what I'm thinking."
Both have made changes to their game this season. Paxton has developed his secondary pitches and Zunino has learned how to be patient and take better at-bats. And that all started down in Tacoma.
"For me, it was his arm slot," Zunino said of Paxton's progress. "He really found that about halfway through April and he's just made great strides. Its still relatively new to him he's still finding some triggers and where to be consistent at but it's been incredible. His velo has come up. His off-speed stuff's been great. And he's pounding the strike zone."
Paxton has continued to develop in the Majors, so Zunino had to adjust his pitch calling Saturday to incorporate the cutter, slider and changeup more. But the chemistry was still intact.
"Once you get to build that relationship and they trust you, that's when it's seamless and [there's] not much shaking off, not much second guessing," Zunino said.
And Paxton said he felt very confident with Zunino behind the plate.
"I know that Z's going to block anything that I throw up there in the dirt," Paxton said. "He's such a great defensive catcher and he does a great job catching the ball back there and calling the game. I really enjoy having him back there."
• Felix Hernandez threw a bullpen before Sunday's matchup with the Orioles. The next step will be a simulated game, which will likely happen on Wednesday in Houston, manager Scott Servais said. Hernandez is scheduled to make a rehab start in Class A Everett on July 10, and a second in Tacoma after the All-Star break.
• After smashing five home runs on Saturday, the Mariners were second in the league in home runs with 122, trailing only the Orioles (127). But Servais said they don't want to let that define their game.
"You don't want to rely on it too heavily because it can go away as quick as it shows up," he said. "You've got to be consistent getting on base, and there's a lot of different ways to score runs, but we need the guys on base."
• Dae-Ho Lee was out of the lineup on Sunday, dealing with a minor hand issue. He was available to pinch-hit.
Maddie Lee is a reporter for MLB.com based in Seattle.