TORONTO -- Shortstop Brendan Ryan and first baseman Justin Smoak both got the day off Sunday as Mariners manager Eric Wedge said both needed a "mental day" after struggling at the plate much of the young season.

Rookie Alex Liddi got the start Sunday at first base and hit cleanup for the first time in his career. Munenori Kawasaki started in place of Ryan at shortstop. John Jaso was in the lineup at designated hitter in place of Jesus Montero, who Wedge said just needs occasional days off due to his youth.

Smoak is batting .187 in 19 games with three home runs and nine RBIs and is just 2-for-27 over the past seven games.

"It's still early," Smoak said. "I'm trying to get squared up on both sides of the plate and I feel like I'm bouncing back and forth every other day. It's one of those things where I'm just trying to find that groove, my rhythm and timing, and it'll come. It's just a matter of time."

Ryan has gone 0-for-17 over the past six games, though he has walked four times and his on-base percentage is still at .290 because he leads the Mariners with 11 walks in 53 at-bats.

He went 0-for-3 with two strikeouts against Toronto's Brandon Morrow on Saturday and acknowledged his frustration was rising.

"I'm just putting myself in a position to not have any success," Ryan said. "I had two strikes in every single at-bat. I'm competing every at-bat. I want the challenge every single time. But when I get the pitch I should hit hard, it's back into the net.

"It's incredibly frustrating because now it seems like he makes a good pitch, I foul one off and now it's an 0-2 or 1-2 count or whatever it may be. At this level, you do that over and over and the percentages are not in your favor, let's put it that way."

Wedge said both Ryan and Smoak would be back in the lineup on Monday when the team opens a four-game series in St. Petersburg.

Smoak did rip a deep drive off Morrow in the fourth inning on Saturday, but it was hauled in at the wall by center fielder Colby Rasmus.

"That's just what happens when things aren't going well," said Smoak. "You hit balls hard and they catch 'em. When it's going good, you break bats and they fall in. That's just the way it goes. But I'm not going to put too much pressure on myself or anything. We're 20 games in. We play 162."

Sherrill to undergo Tommy John surgery

TORONTO -- Veteran left-handed reliever George Sherrill will undergo Tommy John surgery on his throwing elbow early next month and will be done for the season, the Mariners announced Sunday.

Sherrill, 35, will have the ulnar collateral ligament replacement surgery performed May 4 in Los Angeles by Dr. Lewis Yocum.

Sherrill went on the 15-day disabled list on April 13 with a sprained flexor bundle after giving up six hits and four runs in 1 1/3 innings in his first two appearances.

After signing a one-year, $1.1 million free agent contract over the offseason, Sherrill never was fully healthy this spring. He felt some soreness in his elbow while throwing a bullpen session before camp opened in February, then was held back initially.

"I don't think he ever got on track," Mariners manager Eric Wedge said. "There were a few moments where we had some optimism, but it never really got to the point where we felt he needed to get to."

Wedge said he's comfortable for now with lefties Charlie Furbush and Rule 5 pickup Lucas Luetge in the bullpen.

"Those two guys have been doing pretty good," Wedge said. "We've got other guys in Triple-A, but I've been pleased with Furbush and Luetge up to this point. They're both young, but they're finding their way."

Gutierrez's heel an issue; Carp close to return

TORONTO -- Former Gold Glove center fielder Franklin Gutierrez's comeback continues to be slowed in Arizona by a plantar fasciitis issue in his heel.

Gutierrez is on the 15-day disabled list with a partially torn pectoral muscle in his chest and has been working at extended Spring Training with low Minor League players at the team's complex in Peoria. But while his pectoral muscle is nearing full recovery after two months, the heel has become a problem in the past week.

"We're going to give him a couple more days off that heel," manager Eric Wedge said on Sunday. "Right now, we're targeting Tuesday for him to [resume running]. He's still taking batting practice and throwing. That's all good. The heel is the issue now."

Once he's at full strength, Gutierrez will be sent out on a Minor League rehab assignment and likely be given the full 20 days to regain his timing, since he hasn't played much since the start of Spring Training.

Left fielder Mike Carp is closer to returning to the Major League club. Carp, on the 15-day disabled list with a sprained right shoulder suffered on Opening Day in Tokyo, went 1-for-4 with a two-run double for Triple-A Tacoma on Saturday and was scheduled to play designated hitter again on Sunday.

He's hitting just .149 in 47 at-bats, but has hits in his last three games now. Carp's 20-day rehab stint runs out on Wednesday, so the Mariners will need to make some decisions by then.

"We'll revisit that in a couple days, too," Wedge said. "He's playing full games and feels pretty good."

Worth noting

• Mariners starter Blake Beavan has issued just two walks in four starts this season and his average walks per nine innings of 0.7 is the lowest mark in the American League, by a pretty good margin. Colby Lewis of Texas is currently second at 1.1.

• Kyle Seager has six doubles this season and 19 in his first 70 Major League games, which is the second most in franchise history through that time span. Rod Craig had 23 doubles in his first 70 games for the Mariners in 1979-80.