PHILADELPHIA -- Vince Velasquez knows that Sunday’s start at Citizens Bank Park put him in a difficult spot and that he must be better when he starts again, on Friday against the Blue Jays.

“I have to earn my stripes back,” Velasquez said.

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Velasquez’s revamped four-pitch mix and mindset made him one of the Phillies’ best Summer Camp stories. He sounds confident. The Phillies sound optimistic. But he struggled through three innings in his season debut in an 11-6 loss to the Marlins. He allowed three hits, four runs, two walks and two home runs. He struck out four. His outing spoiled a three-run home run from Bryce Harper and handed the Phillies a series loss to a team that lost a National League-leading 105 games last season.

Miami entered the afternoon shorthanded. Its scheduled starter, José Ureña, was scratched in the morning. Harold Ramirez, Garrett Cooper and Jorge Alfaro (Miami's No. 1 catcher) were unavailable after Ramirez and Cooper started the first two games of the series. The Marlins offered no explanation for the absences, although Phillies manager Joe Girardi said the team texted the players 90 minutes before the game because of concerns in the Marlins’ clubhouse. The Phillies reminded their players to be vigilant against the spread of COVID-19. Harper wore a mask on the bases as an additional precaution.

“You have to be safe,” Girardi said. “You can't really have a lot of contact with other people because you put everybody in danger.”

The Phillies left the bases loaded three times and went 2-for-13 with runners in scoring position, but the loss amplified concerns about the pitching -- not only in the rotation but in the bullpen. Cole Irvin, Reggie McClain and Nick Pivetta allowed a combined seven runs in 5 1/3 innings.

These struggles have people looking toward Allentown, Pa., for answers. Top pitching prospect Spencer Howard is part of the team’s 60-man player pool, and he started at the organization’s alternate training site on Sunday afternoon at Coca-Cola Park. The No. 34 prospect in baseball allowed four hits, two runs and two walks in four innings, and he recorded nine total outs in the scrimmage. He struck out four.

It is time?

“That's not something I am aware of as of right now,” Girardi said about a promotion. “My plan is Vince will make his next start, and we'll go from there.”

Howard could have opened the season with the team, but there are service-time considerations. By keeping him off the 30-man roster the first five days of the season, the Phillies gain an extra season of team control. Less than two weeks ago, Harper said on Twitch, “If Spencer Howard isn’t starting in our rotation by Game 6 in New York against the New York Yankees, there’s a problem. That’s all I’ll say.”

The sixth day of the season is Wednesday. Howard is scheduled to pitch again on Friday, which is the eighth day of the season.

Harper will not be frustrated if Howard is not promoted before the end of the weekend.

“I believe in the guys who are on our staff right now,” Harper said. “I believe that we set up our rotation to go out there and compete every single day, and hopefully, they can keep doing that. We have two turns going with [Jake] Arrieta and [Zach] Eflin coming up in a big series against the Yankees. So we’ll see what happens. It’s still a couple days away.”

Girardi and pitching coach Bryan Price said during Summer Camp that Howard will help the big league team at some point. It could be the rotation. It could be the bullpen.

“It’s a thing that we can kind of utilize to kind of learn from each other to make each other better as a pitching staff,” Velasquez said. “I’m not worried at all. My work ethic, I came a long way to earn this spot. I’m still very optimistic in my workability and what I’m capable of doing. Every day is a learning lesson, and [Sunday] definitely kicked my butt a little bit, but I’m definitely very optimistic in myself, my workability, my craft and everything I’ve worked to get to this point.”

Before Velasquez faces Toronto on Friday -- the series will be played in Philadelphia, because the Blue Jays’ temporary 2020 home site in Buffalo, N.Y., is not ready -- the Phillies will play four consecutive games against the powerhouse Yankees. They will need to play much better than they did this weekend.

“We have to put this behind us,” Harper said. “We have to be better as an offense, a defense, pitching the ball, hitting the ball. We just have to be better.”