Under Mahoney, the Saints experienced immediate success and have continued to excel, winning ECAC Upstate Championships in 2001 and 2002 as well as Liberty League titles in 2006, 2007, 2008 and 2009.

Following the 2019 campaign, Mahoney has posted a 242-105 record in the past 22 seasons, with 18 of those teams earning post-season bids including the 2016 team that advanced to the NCAA Tournament semifinal and the 2017 team that advanced to the third round of the NCAA Tournament. Mahoney coached his team to the NCAA Tournament's Second Round four straight seasons ('06-'09) after winning the Liberty League Tournament.

Mahoney has been named the Liberty League Coach of the Year six times in 1999, 2004, 2009, 2012, 2015 and 2016. In addition, he was selected as the Bernie McKinnon Coach of the Year at St. Lawrence in 2015 and was voted the ECAC Metro/Upstate NY Coach of the Year in 2016.

In 2019, the Saints posted a 13-4 record and advanced to the semifinals of the Liberty League Tournament. Senior Zachary Ettinghausen was named USILA/Nike Scholar All-American and was selected to play in the USILA North-South game, while Tyler Burns, Mike Donnelly and Alex Terry all earned All-American Honorable Meniton honors. Seven Saints were named to All-Liberty League Teams, while eight Saints also earned All-Academic honors.

In 2018, the Saints posted a 12-5 record and made a postseason run to the semifinals in the Liberty League Tournament. Senior Jordan Dow earned USILA/Nike Scholar All-American honors, while classmate Sam Boehle and junior Conor Caffrey earned All-American Third-Team and Honorable Mention honors, respectively. Seven Saints were named to All-Liberty League Teams, while seven Saints also earned All-Academic honors.

In 2017, the Saints advanced to the Liberty League championship game for the first time since 2009, earned an at-large bid into the NCAA Tournament and posted a convincing 19-6 win over Monclair State in the second round. Senior captains Conor Healey and Alec Dietsch earned pre-season All-American honors, announced by Inside Lacrosse magazine. Healey also broke a 30-year-old record previously held by Sam Hovey '87 to become the all-time leading point scorer in program history with 291 career points. 10 Saints also earned All-Liberty League honors, while Healey, Dietsch, Andrew Jarrett, Caleb Kane and Jon Fairbanks earned USILA/Nike All-America honors.