Boston’s Opening Day starter Nathan Eovaldi finished in the top five in Cy Young voting last year and hopes throwing more sliders against left-handed batters will help him be even better in 2022. Tony Gutierrez/Associated Press

FORT MYERS, Fla. — The last time the Red Sox had a starting rotation that was better than average, they won the World Series in 2018.

In the three years since, their rotation has ranked 20th, 25th and 17th in ERA, respectively, despite a .521 winning percentage that ranked 13th in that span.

The offense drives the bus for the Red Sox, who rank third in MLB with 5.2 runs per game in that same stretch. And with Trevor Story on his way to Boston to fortify the lineup, scoring shouldn’t be an issue at Fenway Park this summer.

But the starting rotation remains a question mark. Now with Chris Sale shelved for the foreseeable future as he waits for a fractured rib to heal, the Red Sox are prepared to enter the season with a rotation that has a lot to prove.

“We got a bunch of dudes,” Manager Alex Cora said. “Guys who are like 6-foot-6, 6-5, 6’4″. It’s kind of like old school baseball. We’ve been talking about little guys that have fastballs up in the zone; we don’t have those guys. We’ve got big guys, very athletic, very in tune with everything that we do.”

There’s plenty of time between now and Opening Day on April 7 for the Red Sox to change their plans, but as currently laid out during exhibition games, the rotation looks like Nathan Eovaldi (6-2), Nick Pivetta (6-5), Tanner Houck (6-5), Michael Wacha (6-6) and Rich Hill (6-5) piggybacking with Garrett Whitlock (6-5).

It might be the tallest rotation in the big leagues, but there’s more to the story.

After a top-five finish in American League Cy Young voting, Eovaldi thinks expanding his repertoire to include more sliders against left-handed batters will help him be even better in 2022.

Pivetta is coming off a career year, a dominant postseason and the Red Sox love his intensity and aggression in the strike zone, but after several disappointing seasons in Philadelphia, he has a ways to go before he’s considered dependable.

Houck might have the highest upside of the bunch. Breaking into the big leagues and instantly showing one of the game’s best sliders, he has a sky-high ceiling and should finally get a chance to prove himself after being roped between the minors and majors over the last two years.

“We’re getting close to a final product,” Cora said of Houck, a first-round pick out of the University of Missouri in 2017.

Behind the top three is where things get interesting.

Wacha, a first-round pick out of Texas A&M in 2012, was a top prospect coming up through the well-regarded Cardinals system and looked dominant during his first few big league seasons. But his career tapered off from there, and he’s now coming off three seasons in which he has a combined ERA of 5.11. The Red Sox signed him to a one-year deal worth $7 million.

“He will be OK, he will be a good one,” Cora said. “He’s 30. He is still young. He’s still learning.”

Wacha’s fastball averaged 94 mph last year but sat at 94-96 mph during his first spring start on Monday.

“I came in a lot more prepared than I normally would for a regular spring training,” he said.

Hill has been great whenever he’s on the mound, though the 42-year-old is coming off his first 30-start season since 2007. He resurrected his career while with the Sox in 2015. With a low arm angle and one of the game’s funkiest breaking balls, he’s still effective, having posted a 3.86 ERA between the Mets and Rays last year.

“Love the fact that he’s here, still strong,” Cora said. “He’s one of these guys that he’s gonna play as long as he wants.”

Asked if it was weird to manage a guy just four years younger than him, Cora said, “No, no, not really. They respect that line and the way we do things here. … It helps the whole program having guys like that.”

And then there’s Whitlock, the talented Rule 5 pick who had a breakout rookie season last year and is being stretched out to throw more innings in 2022.

At some point around midseason, Sale and James Paxton will join the group as well.

It’s a deeper staff than the Sox have had in years. But on paper, it’s not the best.

Taking the three-year averages of all six pitchers from 2019 through 2021, they have a combined ERA of 4.21, which is even worse than the 4.04 ERA combined three-year average from Boston’s rotation in 2015, the year Clay Buchholz made the “He’s the Ace” T-shirts.

The Sox rotation hasn’t had an ERA under 4.49 since 2018, when their 3.77 mark ranked eighth and led them to a World Series title.

The Red Sox can hit. They can always hit.

Their starting rotation has talent, too. It’s just a matter of putting it all together.

“We have a great starting staff around us,” Pivetta said. “It’s just coming together as a unit and going out and competing every day.”