SEATTLE (AP) — Whether it was intentional or not, Seattle Mariners general manager Jerry Dipoto placed a heavy burden on Felix Hernandez on Thursday.

If Hernandez can stay healthy and be a strong, serviceable arm for Seattle — not the ace he once was — then the Mariners’ questionable pitching rotation may turn out to be just fine. If Hernandez is injury prone and unable to stay on the mound as was the case in 2017, the Mariners could again be scrambling with their pitching staff.

“Nuts and bolts it comes down to how Felix comes into spring training,” Dipoto said during the Mariners’ pre-spring training luncheon. “If Felix can give us the 25 starts or more than he gave us in 2016, we’re going to be a good team. If Felix gives us 16 or less as was the case last year, we’re going to have to answer a lot of questions.”

Putting that on Hernandez shows how tenuous the Mariners’ pitching situation is going into the 2018 season. Seattle seems solid at the top of its rotation with lefty James Paxton and righty Mike Leake. They have numerous options at the back end with Erasmo Ramirez, Marco Gonzales, Andrew Moore, Arial Miranda and Hisashi Iwakuma when he is fully recovered from shoulder surgery.

But the bridge appears to be Hernandez and whether he can evolve in the later years of his career. He’s no longer the ace of Seattle’s staff, but must be a solid contributor in the rotation if Seattle wants to have a chance at competing. A year ago, Hernandez was slowed by injuries and managed 86 innings pitched and a 4.36 ERA — a career low in innings and the second-highest ERA of his career.

“I wish I knew the answer to which of those it is. I don’t, but we’re going to find out pretty quick,” Dipoto said.

As part of helping Hernandez be more prepared for the start of the regular season, the Mariners intend to change his spring training routine. He’ll pitch more and start ramping up well before the final 10 days of spring training. In previous seasons, Hernandez wouldn’t take the mound in a spring training game for about 10 to 14 days after games had started.

Manager Scott Servais said this year will not be that way.

“The first time he takes the mound in the regular season he should be able to throw 100 pitches,” Servais said.

The importance placed on Hernandez only signified the awkward position the Mariners are in as the season approaches. Their everyday position lineup is solid and may be one of the better ones in the American League — led by Nelson Cruz, Robinson Cano, Jean Segura and the addition of Dee Gordon. The bullpen should be a strength after the addition of right-hander Juan Nicasio, the one significant free agent signing made by Seattle this offseason.

But Dipoto was honest that Seattle doesn’t match what Houston has in its pitching rotation; not that many teams in the American League can come close to the Astros.

“The Houston Astros are loaded. I don’t know how else to answer the question,” Dipoto said. “They have a terrific rotation. They have a very good team. Their rotation on paper is as good as anybody in baseball, or better. I don’t think there is a team in the American League West who outpaces us in terms of our starting rotation. I’m not sure of outside of last year’s playoff teams ... I don’t know if there’s another team in the American League that can say definitely that their rotation is better than ours.”

NOTES: Iwakuma has started a throwing program following shoulder surgery late last season, but Dipoto said it would likely be May or early June before the Mariners could realistically expect the veteran right-hander to help the club. Iwakuma signed a minor-league deal to remain with Seattle. ... Gordon said he’s feeling more comfortable with his move from 2B to CF. “I thought it was going to take a little longer for me to convert over,” Gordon said. ... The Mariners are changing some of their workout times to later in the day and playing more night games during spring training in the hope of giving players more rest.