Alonso, the former All-Star slugger for the A's, and Zeile, the former Mets first baseman, were on hand as part of a joint effort between MLB, CVS Health and Cristo Rey to help bring COVID vaccines to an underserved community.
"I think it's very important for the kids here at Cristo Rey High School to have an opportunity to not only know about the vaccine, but also have the ability to get it," Alonso said. "It is very difficult at times to get vaccinated, especially for kids here at Cristo Rey, [with their] busy schedule."
About 75-100 Cristo Rey students, family and faculty members were vaccinated Wednesday afternoon between pre-scheduled appointments and walk-ins, all receiving their first dose of the Pfizer vaccine.
Alonso even got his own first vaccination shot on Wednesday along with the students.
"I think for me it was the opportunity, just like these kids are going to have," Alonso said.
Alonso, who came to Miami from Cuba as a child, said a lot of the students reminded him of his own situation growing up, and he thought coming to Wednesday's clinic and getting vaccinated himself could send a positive message to those students.
Cristo Rey New York serves high schoolers from Black and Hispanic communities whose families have extremely limited financial means and who've been disproportionately affected by the pandemic. The school's vaccination clinic with MLB and CVS helped bring vaccine access to students who might not have otherwise had the information or availability they needed.
"I have a lot of plans coming up during the summer. I plan on traveling. I just wanted to get safe," said 17-year-old Cristo Rey student Christian Avila.
He said it was "really good" that the school set up Wednesday's clinic, because it made getting the vaccine a lot easier for him.
"I didn't plan on getting it, because I didn't really know how to," Avila said. "This was just a very simple way of doing it. I just signed up online and asked my teacher for help. It was just simple and easy. It was really good."
Avila said he was bringing his brother and sister with him to get vaccinated, too, and he saw a bunch of his school friends at Wednesday's clinic when he showed up to get his vaccine. He said it was "awesome" to see Alonso and Zeile supporting the students getting vaccinated.
Alonso and Zeile chatted with many of the Cristo Rey students who were getting their vaccines -- about baseball, about the importance of getting vaccinated and about what their lives have been like over the last year.
"We were really just having a conversation about what it's like to be a high school student right now during the pandemic," Zeile said. "Right now, vaccination is on everybody's mind, and I can't imagine what it's like to be 16, 17, 18 and having to make those considerations."
Receiving the vaccine will help Cristo Rey high schoolers get back into the classroom and back to their work-study programs. At Cristo Rey, students participate in internships at a variety of companies, including Major League Baseball.
Wednesday's clinic with Alonso and Zeile coming to Cristo Rey was just one of MLB's ongoing initiatives to help teams' local communities distribute vaccines, along with others like making vaccines available at ballparks around the country.
"Those guys are terrific," Cristo Rey school president Dan Dougherty said of Zeile and Alonso. "Made our kids feel very comfortable, great stories to tell, and their endorsement of this good public health step can make it all the stronger message for everybody else.
"[Alonso] is being a great model. For him to be an immigrant to the United States as many of our kids are, to be a bilingual speaker, to be a model for our students, very many of whom are Hispanic in background, signals that they can do this, too. He's setting a great example."