This is a predicament many opposing teams have found themselves up against, trying to have some semblance of success against a pitching staff led by Hernandez and Pineda. It's a staff that has essentially kept Seattle -- a team with the fewest runs scored in the Major Leagues -- afloat in 2011.
It should come as no surprise then that the Mariners are represented at the All-Star Game by three guys whose right arms have helped paddle the ship for the past three months -- Hernandez, Pineda and closer Brandon League.
Pineda, the rookie right-hander, was added to the American League team on Sunday as a replacement for Detroit's Justin Verlander. He'll join League as first-timer for the game. Hernandez is here, although he was bumped off the AL roster because he pitched Sunday for the Mariners.
Instead, Hernandez will be rooting on his AL teammates, none more so than the 22-year-old Pineda, who has blossomed into one of baseball's top newcomers this season with an 8-6 mark and a 3.03 ERA.
It wasn't that long ago when Hernandez -- who is 8-7 with a 3.19 ERA and the reigning AL Cy Young Award winner -- was a young pitcher thrust into the spotlight in the Mariners' rotation, making his debut at the age of 19 in 2005.
Pineda, through an interpreter, praised Hernandez for helping make his rookie season as relatively smooth as possible. Hearing this, Hernandez smiled and shook his head.
"He's got a lot of talent," Hernandez said. "I haven't had to help him with a lot of stuff."
Pineda has given the Mariners a tough one-two rotation punch along with Hernandez, as he's racked up 113 strikeouts -- with just 36 walks -- in 113 innings, and opposing batters have hit just .198.
Pineda's 113 strikeouts are the fourth-most by a rookie heading into the All-Star break over the past 25 years, and he's one of four AL starters to record nine starts of six or more innings with one or fewer earned runs, joining Jered Weaver, Trevor Cahill and Verlander.
"He's impressed a lot of people this year," Mariners manager Eric Wedge said recently. "He's learned so much in such a short period of time and he's handled it all well."
League also has burst onto the scene, at least in the closer's role, as he stepped in for the injured David Aardsma and racked up 23 saves over the first half, good for second in the AL.
But don't blame League if he's a bit distracted this week, however. His wife, Sasha, is pregnant with their third child and due any day. Sasha is in Phoenix with family for the week, so League won't have to go far if he's needed.
As for League, who was obtained by the Mariners from the Jays in a deal that involved pitcher Brandon Morrow in December 2009, a trade that was unpopular at the time, he's thankful for the opportunity to show what he can do at the end of a game.
"I was very fortunate to set up for Aardsma last year, and fortunate I was given the chance to close this season," League said.
Joyce and his Rays teammates might not be so lucky later this month when they head to Seattle. Chances are, if they don't see League at the back end of a game, they'll certainly get either Hernandez or Pineda, or maybe both.
"I didn't get a chance to face Pineda, but watching his stuff ... it's electric," Joyce said. "But I did get a chance to face Felix for the first time in Seattle, and I was trying to get him before he got me.
"If he threw it over the plate I was trying to put it in play, because you know what kind of stuff he has."