FORT MYERS, Fla. -- Bryce Harper is signed and sealed, and on Sunday, he delivered his first batting-practice swings of spring training. And so, we return you to your regularly scheduled Phillies programming, including the biggest question entering the franchise’s most hyped season since 2011.

Do they have enough starting pitching?

Jake Arrieta thinks so. He’s biased, of course, as one of the five holdovers from last season’s starting rotation. But it hasn’t escaped the veteran right-hander’s notice that the Phillies improved the roster in every possible area -- infield, outfield, relief pitching, even catcher -- except for one: the starting rotation.

“I think we all have that collective mindset -- OK, they’re going to give the same five guys the ball,” Arrieta said after tossing three perfect innings here Sunday in a 3-3 tie with the Minnesota Twins. “It looks like it’s going to be the same five guys, and I love that. I really do.”

The Phillies made a push in November for prized free-agent lefty Patrick Corbin. They hosted him at Citizens Bank Park and splashed his photo on PhanaVision in left field but refused to match the Washington Nationals’ six-year (and $140 million) guarantee. And although they had some interest in lefty J.A. Happ, it wasn’t enough to keep him from re-signing with the New York Yankees.

Beyond that, the Phillies shrugged at other free agents. Wade Miley? No, thanks. Gio Gonzalez? Pass. Dallas Keuchel? Not for the kind of contract that he wants. Simply put, they don’t view any of those pitchers as an upgrade over what they have.

“What it tells all of us is that [general manager] Matt [Klentak] was going to look under every stone to improve our roster, and this was the area he felt confident enough in to say, ‘These are the guys we want to go to battle with,’” manager Gabe Kapler said. “I think everybody in our clubhouse feels the same way.”

» READ MORE: Jake Arrieta throws three perfect innings in first spring-training start

Arrieta sees it as a vote of confidence for young right-handers Nick Pivetta, Vince Velasquez, and Zach Eflin, all of whom he believes “have a couple more steps to take throughout the progression to get to their peak.” But he also takes it as a personal challenge to be better and more consistent, no small thing for a former Cy Young Award winner.

Last year, his first season with the Phillies, Arrieta alternated solid months with lousy ones until, like the rest of the team, he completely fell apart down the stretch. His ERA by month: 3.49 in April, 0.90 in May, 6.66 in June, 2.80 in July, 4.50 in August and 6.39 in September, with his lasting impression being a two-inning, four-run implosion in a must-win game on Sept. 22 in Atlanta.

In hindsight, Arrieta attributes his late-season fade to a left knee injury that he concealed from team officials, including Kapler, until January when he elected to have surgery to clean up a meniscus tear.

» READ MORE: Bryce Harper signing ushers in a new era for Phillies’ longest-tenured players

But Arrieta, who turns 33 on Wednesday, revealed something else on Sunday. For a while now, he has pitched from a different arm angle than the three-quarters slot that he used in his best years with the Chicago Cubs. He’s not sure how it happened, only that he fell into a bad habit that wasn’t easily corrected in the midst of a season.

“From Day 1 in spring, I reestablished more of that high three-quarter arm slot, which creates much more downward movement on the sinker, the cutter and the change-up,” Arrieta said. “That's kind of where I was in '15 and '16. To get back to that feels really good. I think just having a full spring training is one big reason why I'm able to kind of get back on track right away.”

Seeing is believing, and in his spring debut, Arrieta couldn’t have looked better. He faced nine Twins batters, most of whom were lineup regulars, and retired them all in just 34 pitches. He touched 94 mph, according to the Hammond Stadium scoreboard, and mixed in breaking pitches that elicited awkward-looking swings.

It was a good first step.

“There's a healthier Jake, a more motivated Jake, a more focused Jake,” Kapler said. “And it all begins with health because health always leads to confidence, and in my opinion, action and confidence leads to more motivation. So you can see that kind of snowballing.”

If it filters down to Pivetta, Velasquez, and Eflin, so much the better. But a bounce-back from Arrieta will be as central to the Phillies’ rotation question as anything else.