Stan Kowalski, a World War II veteran from Blaine who became a popular professional wrestler, died Friday. He was 91.

Kowalski was born Bert Smith, but Minnesotans knew him primarily as the “Krusher,” “Killer” or “Big K” — part of a pro wrestling tag team called Murder Incorporated. But it was his work after leaving the ring that left the most lasting impact.

“Wrestling certainly opened so many doors,” said his son, Scott Smith. “As much as the older generation loved him for that, giving back was more important to him.”

Kowalski dedicated himself to public service — raising millions for Greater Twin Cities United Way and fiercely advocating for veterans, especially homeless vets.

“He’s taken his retirement from wrestling and turned it into a win-win for veterans to get access to health care, to help those who are homeless and to push for recovery of service people missing in action,” U.S. Rep. Betty McCollum, D-Minn., said in a 2004 Star Tribune article.

Kowalski enlisted in the Navy as a 17-year-old and served on three submarines as a gunner’s mate.

Up until a few months ago, he was still active in veteran affairs. He was in a parade nearly every weekend this summer with submarine veterans, participated at the Memorial Day event at Canterbury Park Racetrack and Casino and attended Military Appreciation Day at the State Fair.

In 2004, Kowalski drove a dozen times to Camp Ripley in Little Falls, Minn., and to the Air Force Reserve’s 934th Airlift Wing to see off troops headed to Afghanistan, Kosovo and Iraq.

“Because he himself, being a Navy man and a veteran, he just started doing whatever he could to help,” said his daughter, Stacy Smith.

In an interview with the Star Tribune in 2011, Kowalski said he was 5 feet 10, 160 pounds when he entered the service and 6 feet 3, 250 pounds when he left. He then enrolled at the University of Minnesota, where he studied journalism and continued to wrestle.

He changed his birth name from Bert Smith to Stan Kowalski. During his 26-year career, Kowalski won 19 major titles and wrestled in 6,600 professional matches. (Another wrestler, Reginald Lisowski, who died in 2005, became famous under the moniker the “Crusher.”)

In the ring, Kowalski dressed in black and chased opponents out of the ring, slamming them with folding chairs or bashing them while his tag-team partner, Tiny Mills, held them against the ropes. Crowds loved to hate him. But after matches, he would sign autographs and do magic tricks for the kids until the last fan went home.

“The community has lost a pillar and a great friend; the world has lost a hero. He is known all over, but my brother and I have lost our dad,” Stacy Smith said.

The beginning of his retirement wasn’t easy. The then-50-year-old had spent his entire career on the road. “He had to reorient himself,” Scott Smith said.

So he volunteered for the United Way. After 50 years, he became the organization’s most prolific speaker in the Twin Cities. He raised millions of dollars for the organization and delivered 15,000 speeches, said Sarah Caruso, Greater Twin Cities United Way president and CEO.

“It’s what his journey on this Earth was ... it was compassion and to help people,” Stacy Smith said.

In addition to his daughter and son, Kowalski is survived by four grandchildren. His wife, Cleo, preceded him in death. Services will be held at 11 a.m. Friday at Living Word Christian Center, 9201 75th Av. N., Brooklyn Park, with visitation starting at 9 a.m.