"He's not going to be overwhelmed by anybody," McClendon said. "He's a crafty veteran. I've always liked his bat. He knows what he's doing. He has the ability to put the bat on the ball. There's kind of a calming effect to a lineup when you've got Endy Chavez in there."
Chavez hit .267 in 97 games for Seattle last season and re-signed with the club this spring on a Minor League deal that contained a June 1 opt-out clause. If Chavez wasn't on the Mariners' Major League roster by Sunday, he would have been free to sign elsewhere.
The 12-year veteran, who also played for the Mariners in 2009, said he appreciates getting another shot with Seattle instead of seeing what options he might have had on June 1.
"That was the thinking of my agent, but I'm glad we don't have to worry about that," he said of the opt-out date.
Chavez hit .272 in 30 games with Triple-A Tacoma, while also helping mentor some of the young outfielders, including recently promoted center fielder James Jones. And that's another reason the Mariners like having him around their young club.
"I know I like to play baseball the right way and that's what I try to explain and teach to the young guys," Chavez said. "I was with JJ down there a little bit and we talked a lot. He's a good player. I like him and he can do a lot of stuff, so I've been watching him and helping take care of him. We have very good communication. Besides that, I want to put up some numbers so I can help the team, too."
For the moment, Chavez's addition gives Seattle six outfielders, four of whom are left-handed hitters with Jones, Dustin Ackley and Michael Saunders also filling that role. Stefen Romero and Cole Gillespie are the only right-handed-hitting outfielders.
McClendon acknowledged the glut of outfielders, but said it wasn't an issue for now.
"I think we can make it work," he said. "We've got some Interleague Play coming up where we'll need the extra player. So we'll see."
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.