Zach Bryan pays tribute to NYPD's Jonathan Diller at UBS Arena concert

In his two-night stand at UBS Arena in Elmont this weekend, country music star Zach Bryan paid tribute to fallen NYPD Officer Jonathan Diller, sang a duet with Mets first baseman Pete Alonso, and spotlighted local musician Sarah Gross by bringing her onstage to perform a song with him.

On Saturday, as captured by audience video, Bryan told the audience, "I got some really bad news this morning. Someone told me there was an officer named Jonathan Diller who passed away in the line of duty. He was from Long Island, right here," the singer-songwriter, who turns 28 on Tuesday, continued, as an image of Massapequa Park's Diller appeared on the arena's jumbo screen.

"And I want to say that this is heartbreaking, and I can’t even imagine," he stated. "So I’m going to try my best to sing this without messing it up. Just know that I respect and love you guys so much. I'm so sorry.”

Bryan then performed the somber "Jake's Piano: Long Island," about carrying on after the departure of a loved one. Afterward, as Diller's image returned to the screen, Bryan said, “That's for Officer Jonathan Diller. And any cop, any EMS, any first responder, we love ... you. Seriously. You’re so brave."

Diller was fatally shot on March 25 during a traffic stop in Far Rockaway, Queens. His partner, Officer Veckash Khedna, shot the suspected assailant, Guy Rivera, who was hospitalized and charged Thursday with first-degree murder.

On a much more upbeat note, Mets slugger Alonso, 29, joined Bryan onstage, for a rambunctious rendition of the performer's 2020 number "Revival.” Alonso, who that afternoon had hit his first home run of the year in the Mets' 7-6 loss to the Milwaukee Brewers, has not commented on social media.

And on Sunday, Holbrook singer-songwriter Sarah Gross was invited to go onstage with Bryan and perform his and Kacey Musgraves' No. 1 hit "I Remember Everything."

That evening's duet came about, said the Brookhaven-born Gross, 24, when she met Bryan's father, Dewayne, during a preshow tailgate party he organized and hosted outside the arena. "And he has an East Moriches Fire Department shirt on. I thought, 'How weird. He's all the way from Oklahoma — how could he know someone in East Moriches?' " She went up to him to ask and learned it was "simply that some firefighters had handed him the shirt."

They got to chatting "and he says, 'Why don't you go up and play a couple of songs' " like other local performers in the informal lineup. Sitting atop a picnic table, Gross played some tunes "and then Dewayne pulls me aside and says, 'Hey, why don't you come back tomorrow for the pre-show? … And I'll get you tickets into the show.' "

Gross did so, bringing her parents, Ron and Wendy Gross, of Mastic Beach, and performed at the tailgate party. "And I was thrilled just to do that. And then we're going into the concert and I get a phone call from Dewayne saying, 'Hey, I sent Zach a few videos of you singing and he'd like to sing "I Remember Everything" with you tonight.' " Gross, who has released singles including "Naturally" and "Brooklyn (Only Rains)," went on to meet Bryan and got set up with in-ear monitors, and then "just kind of walked onstage and sang it with him."

As she did so, "I thought, 'I have two ways I could look at this' " — with either anxiety or " 'as the most fun I'm ever going to have in my life.' I just wanted to soak up and enjoy every moment. And it felt so cathartic and full circle to be on that stage. I wasn't super nervous, surprisingly. I think I just have worked so hard playing these gigs" all over Long Island and New York State "and doing what I've been doing. And I realized I was where I was meant to be in that moment."

Gross next plays a free show Thursday at Spotlight at The Paramount, in Huntington, to promote her album "The Killjoy."