TACOMA, Wash. -- The Mariners gave their fans two more reasons to tune in down the stretch on Tuesday, as manager Scott Servais announced that Félix Hernández and Justus Sheffield will join the rotation for the upcoming weekend series against the Blue Jays.

Seattle’s reunion with its veteran star and its No. 9 prospect per MLB Pipeline has been a long time coming. It will be welcome relief to a rotation that has survived on a mix of starters and openers since injuries took over.

It will also allow Yusei Kikuchi another planned rest, as Sheffield will take Kikuchi’s start on Friday at T-Mobile Park.

Hernandez's rehab start for Triple-A Tacoma on Monday represented his final hurdle before returning to a Major League mound, and he believes he cleared it.

Hernandez exited after issuing back-to-back walks to begin the fourth inning, coming one pitch shy of his threshold of 70. The three-plus innings were two frames short of what the Mariners hoped he could pitch. Hernandez's fastball sat in the high 80s and topped out at 91 mph, and his command evaded him early and late, though both Tacoma and Salt Lake showed frustration with home-plate umpire David Arrieta Quintero’s strike zone.

Servais was a bit less concerned with stats and more with how the 33-year-old felt during and after the outing, though he did note that the intensity level of Hernandez’s start was “really good.”

“Command of the fastball, as expected, wasn’t as pinpoint as he would’ve liked it, but he felt healthy,” Servais said. “That was all good there, so he will slide into our rotation.”

Hernandez scattered four hits, allowed one run and struck out five, including three on the curveball that will account for a bulk of his pitches against big league hitters.

“What else do I got to show them to be up there?” said Hernandez, who has completed four rehab outings. “I mean, I feel pretty good and I'm ready to go.”

The Major League veteran -- who racked up career strikeouts No. 2,500 and 2,501 in his last outing on May 11 -- is slated to start Saturday.

Sheffield is 7-9 with a 4.13 ERA in 24 starts between Double-A Arkansas and Triple-A this season. The left-hander made his MLB debut in an April 26 spot start against the Rangers, allowing two runs on two hits and four walks over three innings. He was optioned to Tacoma the following day.

Servais said then that he’d prefer to let Sheffield continue to “work on things” rather than to shuttle him between levels. “We’d like to call him up and leave him here and let him go,” Servais said.

At long last, it seems there’s no better time than the present for Sheffield to get a jump-start on next season.

Seattle has been operating on a four-man rotation since trading Mike Leake on July 31 thanks to a bevy of off-days, but that tactic wasn’t going to be sustainable beyond its upcoming six-game homestand.

Nonetheless, Hernandez’s three-month recovery from a right shoulder strain is winding down in unison with the Mariners’ season and, in all likelihood, his tenure with the team. Hernandez is earning $27.858 million in the final season of a seven-year contract, and given the direction that the club is headed -- attempting to shed payroll and allocate playing time to players it's developing -- Hernandez doesn’t align with its long-term plans.

“I can't wait to go up there and pitch,” Hernandez said. “It's going to be my last year. I don't know what's going to happen next year, so I'm going to go up there and show them that I still love the fans and that I still love Seattle.

“It's been frustrating. It's been tough on my mind. But you know what, to get to forget about it, we've got a month and a half left, I'm just going to go out there and pitch.”

Beyond the health of his shoulder, Hernandez is trying to prove to Mariners management that he warrants Major League innings -- perhaps once unthinkable when he was dominating the American League over a decade-plus peak, headlined by winning the 2010 AL Cy Young Award and throwing the Majors’ most recent perfect game on Aug. 15, 2012.

Hernandez has also been one of the most beloved players in franchise history for his engagement and loyalty, having spent each of his 15 seasons with Seattle. And he has been one of its most reliable, hitting the injured list just twice during his first 11 seasons, when he led Major League pitchers with a 52.7 WAR, per FanGraphs, and compiled the third-most innings with 2,262 1/3.

Yet Hernandez’s drop-off has been stark. His 4.79 ERA in the four seasons since (2016-19) is the 15th highest among 106 qualified starters, and he was 1-4 with a 6.52 ERA in eight starts to open ‘19 before his IL stint. Even while acknowledging that he has “got a lot of miles” on his arm, Hernandez would still like to pitch in the Majors in 2020. He’ll have a little more than a month to audition.

Other injury updates from Tacoma
• Right-handed reliever Austin Adams (right shoulder strain) threw a 20-pitch live batting practice session on Monday, which is typically one of the final precursors to beginning a Minor League rehab assignment. Adams had been arguably the Mariners’ best reliever before suffering his injury on July 6.

• Right-handed reliever Dan Altavilla (right forearm strain) will likely pitch another rehab outing on Tuesday for Tacoma, where he has made two appearances after one at Class A Short-Season Everett.

• Haniger (lower back) was still experiencing soreness on Monday and was not in Tacoma. Servais over the weekend likened Haniger’s status to being at the onset of Spring Training, where players are still conditioning themselves for everyday demands.

• Second baseman Shed Long (fractured right middle finger) remains at the club’s Spring Training facility in Peoria, Ariz., where he’s working out. Seattle is hopeful that Long might return this season, potentially for Arkansas’ bid in the Texas League playoffs next month.