MIAMI -- Eight years ago, Marlins reliever Tommy Nance, then a student-athlete at Santa Clara University, decided to surprise his family with a visit. Except no one was home. He waited outside for a bit before calling his father.

It was then that his dad, Mark, broke the news. He had been diagnosed with Amyotrophic lateral sclerosis (ALS), sometimes called Lou Gehrig’s disease. It is a rapidly progressive, invariably fatal neurological disease that attacks the nerve cells responsible for controlling voluntary muscles.

• MLB to celebrate 2nd annual Lou Gehrig Day

"It was really tough to hear at first, but he's a fighter," Nance said. "He's always tried to keep a positive mind-set. It is difficult, obviously on family caretakers. You don't realize that side of it until you see it. And for me being gone eight months out of every year, when I come home, it's hard because there's a level of guilt there because I'm not there. But I know that he is my biggest supporter and wants me to do what I'm doing. This is my dream.

"It's definitely difficult. Luckily, he started to decline quickly at first, and then it plateaued and it's been very slow progressing. I know that there are some people who have lived with it for 10-plus years, and some more it's been six months. So it really just depends."

An Air Force veteran and a retired firefighter, Mark is "physically the strongest person I know," according to Tommy. Mark isn't capable of doing what he used to from a physical standpoint, but his mental strength is as strong as ever.

Even though Nance can't be around to support his father as much as he would like, he does what he can. During his rookie season with the Cubs in 2021, he connected with Marquee Sports Network broadcaster and former Marlins radio voice Jon "Boog" Sciambi on Project Main Street, whose mission is to improve the quality of life for individuals afflicted with ALS and their families by lessening the financial burden associated with this devastating disease. No cure has been found for ALS, and about 10% of those individuals survive for 10 or more years.

The Cubs flew out the Nance family for the inaugural Lou Gehrig Day last June at Wrigley Field, and Tommy recorded the hold in a 6-1 victory. Mark provided inspiring words of never being out of the fight, pushing on and fighting the disease.

Over the offseason, Tommy spent time at his Long Beach, Calif., childhood home, where a years-long remodeling project was finally completed. It accommodates Mark's condition with expanded hallways and more room for his chair. Nance also got involved with Major League Baseball's ALS committee.

Thursday marks the second annual Lou Gehrig Day, which aims to honor the Hall of Famer’s legacy, raise awareness and funds for research of ALS and celebrate the groups and individuals who are leading the pursuit for cures.

The Marlins have dialed up the activations with Nance part of the organization. The club will host patients and their families at Thursday's game against the Giants at loanDepot park, including batting practice and recognizing them pregame. Miami also will provide a Permobil wheelchair to a Marlins fan with ALS in need. During the game, the Marlins will acknowledge the work of The ALS Center at UM during their Marlins Impact Moment feature on their video board. And the Marlins and the Dan LeBatard Show will partner on an awareness campaign/telethon.

Since travel, especially a cross-country flight, is difficult for Mark, the Nances will watch from afar this Lou Gehrig's Day. Tommy, who has posted 13.5 strikeouts per nine innings and a 3.60 ERA in eight outings with the Marlins, saw his father last month when the family drove down to San Diego for a road series at Petco Park.

This past weekend in Atlanta, Tommy began wearing a T-shirt that Sciambi had made in each ballclub's colors. Tommy's fellow relievers and shortstop Miguel Rojas began sporting them. Tommy hopes wearing the T-shirt will spark a conversation, just like the viral ALS ice bucket challenge of 2014. With those funds, Mark was able to participate in a study.

"My ultimate goal is to get everybody in the league to wear No. 4 on that day every year," Nance said. "I'm surprised we haven't done it yet. It actually kind of blows my mind."