Ward played for the Orangeville Northmen Jr. A from 2008 to 2012. During that time the Northmen went to the provincial finals all five years, won four provincial championships and three national championships. He was named Junior Goalie of the Year and Junior Player of the Year in 2010 by Inside Lacrosse. magazine, received the , and won the Most Valuable Player of the Minto Cup Tournament in 2012. In 2009 he played for Team Ontario at the U19 Canadian Field Championships. Ontario won the title and Ward was named Most Valuable Player of the tournament. In the 2013 Major Series Lacrosseentry draft he was selected forth overall by the Kitchener-Waterloo Kodiaks and played for them in the 2013 and 2014 seasons.
The Ohio Machine drafted Ward in the 2013 MLL collegiate draft and subsequently traded him to the Hamilton Nationals. He played with the Nationals during the 2013 regular season and the semi finals of the MLL 2013 Championship weekend where they were eliminated by the Chesapeake Bayhawks. On July 20, 2013, Ward recorded 21 saves against the Machine earning him of thirteen highlight plays of 2013 in the MLL. The Hamilton Nationals suspended play after the 2013 season and his rights were transferred to the Florida Launch. Although he did not play in the 2014 season, the Launch protected his rights for the 2015 season. On December 17, 2014, the Denver Outlaws announced that they had traded Charlie Cipriano and Curtis Dickson to Florida for Ward and two fourth round picks in the 2015 MLL Supplemental Draft.
PLL
On March 10, Ward was announced as one of sixteen players who would be transferring from MLL to the Premier Lacrosse League. Six days later, he was selected by Chaos with the seventh overall pick in the PLL Entry Draft.
NLL
The Colorado Mammoth selected Ward third overall in the 2013 NLL entry draft. He played for them during the 2014 season, ultimately earning the role of starter. He was named Rookie of the Year in the NLL by Inside Lacrosse magazine and was runner-up as NLL Rookie of the Year and named to the NLL All-Rookie Team. On September 18, 2014 the Mammoth announced that Ward had signed a five-year contract with the team. In 2016, Ward was a second team all-pro. In 2017, Ward won Goaltender of the Year and was a first team all-pro. In 2018, Ward was second team all pro again.
International
Ward was selected to play for Team Canada at the FIL 2014 World Lacrosse Championship in Denver, Colorado. Ward started in all seven games that Canada played, winning six and losing one. On Saturday, July 19, 2014 Canada defeated the United States 8-5 to win gold. Ward was named Outstanding Goalie, to the All-World Team and of the tournament.
