“THANK YOU.”
Those were the words Philadelphia Waterdogs coach Bill Tierney and general manager Dave Cottle exchanged as they embraced during the final moments of the 2026 Premier Lacrosse League championship game at Sports Illustrated Stadium in Harrison, New Jersey.
“The only reason I came back [to pro lacrosse] was to help Billy win a championship,” Cottle said. “Everybody knows how hard it is to win a championship. It seldom works as quickly as this one did.”
Tierney is no stranger to winning championships. He won six NCAA Division I titles at Princeton and another at Denver. But this one, his eighth overall, was a far different experience.
“We went 2-8 my first year, and you could look at it as a complete failure,” Tierney said. “In another way, it was the spark that ignited the realization that we had to change some things.”
It was all about learning — and learning that he had to learn.
“When you've been doing this for over 50 years, you think you have a blueprint, and all of a sudden, you get thrown into a situation that's just a little bit different,” Tierney said. “I learned a lot from our players and Coach Cottle.”
Cottle, 70, and Tierney, 74, as decorated a pair as you can get in lacrosse. Cottle had three titles of his own to his name before the Waterdogs’ 14-4 win over the Denver Outlaws, claiming three Major League Lacrosse crowns as the head coach of the Chesapeake Bayhawks.
This championship was their first together. It was the product of a 43-year friendship and pairing of two of the most influential coaches in lacrosse history.
Tierney, a Long Island native, is the most accomplished coach in NCAA Division I men’s lacrosse. After a long career as the head coach at Loyola and Maryland, the Baltimore-born Cottle found sustained success in the MLL. He’s still the only head coach in professional field lacrosse to win three championships. They co-founded the Top 205 Lacrosse Camp, an invitation-only recruiting and instructional camp that originated on a hotel napkin in 1989 and unearthed countless All-Americans for college coaches to discover.
Their success isn’t their only bond. Both were retired. The game called them back.
After retiring from college coaching in 2023, Tierney was hired to coach the Waterdogs less than a year later. Cottle stepped down as the Bayhawks coach after winning his third championship in 2019, but he returned to the sidelines in 2024 to serve as Navy’s offensive coordinator. In 2025, the longtime friends finally joined forces.
“Dave really helped us with his personnel acumen,” Tierney said. “I struggled with the hard parts of the job, which were not the X's and O's, but cutting guys, drafting guys and telling six guys that they weren’t playing on Saturday. Dave had no problem with that, and he was always honest with the players.
“He would always say to me, 'I'll get you the guys, but you got them on Saturday.’”
Legends of the Game
Dave Cottle and Bill Tierney are two of the most decorated coaches in lacrosse history and added to their resumes by winning a Premier Lacrosse League title with the Philadelphia Waterdogs in September.
Hiring Cottle wasn’t always the plan. Tierney was hired to be both the head coach and general manager, but at the end of his second season, the PLL front office offered him the chance to hire a GM.
“They said, ‘What do you think about hiring a GM?’ and I said, ‘I think I quit,’” Tierney said.
After a quick back-and-forth, Tierney said he’d only hire a GM if he was allowed to pick who it was.
“They didn’t know what they were getting into when I told them Dave Cottle,” he said.
Cottle said “yes” immediately and wasted no time getting to work, targeting reigning defensive player of the year Gavin Adler in free agency.
Acquiring Adler not only improved Philadelphia on the field, but it sent shockwaves through the PLL. By many accounts, he was the top free agent available. And Philadelphia desperately needed all the help it could get.
“Not only did we take the best defenseman off a championship team, but we also took Gavin off of Michael Sowers,” Cottle said. “When we played the Atlas [this year], they didn't have a guy who could really cover Michael. It was an opportunity to hurt our rival and help ourselves.”
After the Adler signing, Cottle and Tierney directed their attention toward the PLL College Draft. Their monthly calls quickly became daily ones.
“Billy and I watched a ton of lacrosse games, and we came up with 20 guys that we felt could help us,” Cottle said.
Cottle’s preparation for the 2026 PLL Draft started even before he was hired. He watched the PLL from afar. And after a game against Johns Hopkins when he was still on the Navy staff, Cottle recalled approaching Matt Collison after the Canadian attackman had one goal and one assist in a 10-9 loss to the Mids.
“When the game was over, I walked up to Matt Collison and said, ‘Who the heck are you and where are you from?’ It was obvious to me he was going to be a phenomenal player,” Cottle said.
Without even knowing it, Cottle had scouted one of Philadelphia’s six 2026 rookies, all of whom made an impact on this championship team.
Each of Philadelphia’s four rookies on offense had at least a point in the semifinals against the Boston Cannons, with Kyle Lewis and Josh Yago producing three points each. In the championship game, Collison and Silas Richmond registered the final two goals.
The Waterdogs’ selection of Cornell defenseman Brendan Staub flew under the radar. Cottle and Tierney credited extensive discussions with Adler and league MVP CJ Kirst before the draft for influencing their decision to draft Staub 23rd overall.
Staub was well worth the choice.
“Gavin and CJ sold us on taking Brendan Staub,” Cottle said. “They said, ‘Coach, you're going to love him. He plays hard. He's tough. He can play pole or close. He's a great teammate.’ I don't think we lost a game when he moved down low for us. And then fast forward, he scores a goal in the championship.”
Rookie goalie Sean Byrne might have made the biggest impact. Cottle had every intent of taking him, but when he and Tierney got the sense that no one was drafting a goalie, they gambled. They decided to wait until after the draft and sign Byrne as an undrafted free agent.
When incumbent starter Matt DeLuca went down with an injury, Byrne took over and led Philly to seven straight wins, including the championship victory. He saved 68.4 percent of shots and helped the Waterdogs hold the Outlaws to the lowest goals total in a PLL championship game.
“As a group, those six young men ignited the older guys,” Tierney said. “It wasn’t just the lacrosse. It was the energy that they brought to the team.”
Philadelphia already had two established stars. Kirst and Sowers, who combined for 11 points in the title game, are players Cottle called “force multipliers.” They were neck and neck as PLL MVP finalists, a nod that went to Kirst after he set the single-season record with 34 goals.
“There are very few people in this world that make everybody on the field better and make everybody on the field feel like they're the most important guy on the field,” Cottle said. “CJ Kirst and Michael Sowers did that this year.”
In Cottle’s final game as a head coach, the Bayhawks defeated the Outlaws in the 2019 MLL championship game. Nearly seven years later, another Cottle-built team defeated Denver in a title game.
Days after winning the title, Cottle was already thinking of how to tinker with the roster for next year.
“We have a couple of guys we'd like to sign to multi-year contracts. So, we're working on that,” Cottle said. “And then we're going to look at free agents and try to find the guys that fit the type of teammates, the kind of athletes, the kind of toughness we want.”
Tierney intended to take a little more time off. He planned to travel to Hawaii with his wife, Helen, to celebrate their 50th wedding anniversary. He also wants to work on his book, which he started writing three years ago.
“The good news is I'm 390 pages in. The bad news is I'm only up to the year 2001,” he said.
Writing is cathartic for Tierney. He wants to write something for his children — two sons (Brendan and Trevor, teammates on Princeton’s 2001 NCAA championship team) and two daughters (Courtney and Brianne) — and grandchildren.
“I talked to one of my favorite players from my '92 Princeton team, Evan Garfein, and then, 20 minutes later, I'm talking to Michael Sowers,” Tierney said. “I've been let into these guys' lives, and hopefully, gave them a little bit along the way. When you go into this profession, you realize very quickly that you have the support of the people that mean the most to you, which is your family and your friends.”
This PLL championship was another fitting chapter in an unmatched coaching career — even it means a little more time before that book goes to press.
“The G.O.A.T. is still the G.O.A.T.,” Cottle said.
