Zachary Kenneth Werenski (born July 19, 1997) is an American professional ice hockey player who is a defenseman and alternate captain for the Columbus Blue Jackets of the National Hockey League (NHL). Drafted eighth overall by Columbus in the 2015 NHL entry draft, Werenski has become one of the most accomplished players in franchise history. In 2026, he won the James Norris Memorial Trophy as the NHL's top defenseman. Werenski was co-recipient in June 2026 of the Excellence in Sports Award from the National Polish-American Sports Hall of Fame in Troy, Michigan.
Following his draft selection, Werenski joined the Lake Erie Monsters and helped lead them to the 2016 Calder Cup championship. He made his NHL debut later that year and was named a finalist for the Calder Memorial Trophy as the league's best rookie in 2017. Over the following decade, Werenski established himself as one of the league's premier offensive defensemen, earning multiple NHL All-Star selections and becoming the Columbus Blue Jackets' all-time leader in assists, points, and goals among defensemen.
Internationally, Werenski represented the United States at the 2015 and 2016 World Junior Championships. In the 2025 World Championship, he helped the United States capture its first gold medal in the World Championship since 1933 and was named the tournament's best defenseman. At the 2026 Winter Olympics, he assisted on Jack Hughes' overtime winner against Canada, helping the United States win its first gold medal in the Winter Olympics since 1980.
Werenski played in the 2009 Quebec International Pee-Wee Hockey Tournament with the Detroit Belle Tire minor ice hockey team. He later trained with the USA Hockey National Team Development Program during the 2013–14 season. He finished second among team defensemen in scoring with seven goals and 20 assists in 47 games, despite missing time in November due to injury.
During his freshman season, at the University of Michigan, Werenski recorded nine goals and 16 assists. Following an outstanding rookie season, Werenski was named to both the 2014–15 Big Ten All-Freshman Team and the All-Big Ten First Team. Werenski's CHL rights were owned by the London Knights of the Ontario Hockey League. He was drafted by them in the 2013 OHL Priority Selection.
Following an outstanding season with the Wolverines, Werenski was named the Big Ten Conference Defensive Player of the Year and was named to the All-Big Ten First Team. Werenski was the No. 1 scoring defenseman in the Big Ten and was second in the nation among blueliners in points with a career-best 11 goals and 25 assists in 36 games. His six power-play goals put him No. 2 in the nation among defensemen. He had 51 blocked shots on the season and became the 18th defenseman in Michigan history to record 10 goals in a single season and the first since Jacob Trouba scored 12 goals in 2012–13 season. He was also named an AHCA First Team All-American.
During the 2016 Big Ten Men's Ice Hockey Tournament, Werenski and Kyle Connor tied the record for most assists in the Big Ten tournament championship game with three assists. Werenski and Connor also tied the record for points in a championship game with four points. He was also named to the Big Ten All-Tournament Team.
On June 26, 2015, Werenski was drafted eighth overall by the Columbus Blue Jackets in the 2015 NHL entry draft.
On March 29, 2016, Werenski signed a three-year, entry-level contract with the Columbus Blue Jackets, beginning with the 2016–17 season. He was signed to an American Hockey League amateur tryout contract with the Lake Erie Monsters, the AHL affiliate of the Columbus Blue Jackets.
He made his professional debut for the Monsters on April 1, 2016. On April 9, he scored his first professional goal, the overtime game-winning goal against Nathan Lieuwen of the Rochester Americans. During the 2016 Calder Cup playoffs, Werenski recorded five goals and nine assists, to help lead the Monsters to their first Calder Cup championship.
On October 13, 2016, Werenski made his debut for the Blue Jackets in the season opening-game and scored his first NHL point with an assist. On October 15, 2016, in his second NHL game, Werenski scored his first goal against Martin Jones of the San Jose Sharks. Werenski was named the NHL's Rookie of the Month for November 2016. Through 14 games that November, Werenski scored three goals and seven assists.
On March 10, 2017, Werenski set the record for the most points scored by any Blue Jackets rookie in franchise history beating the previous record holder, Rick Nash, by 8 points.
Werenski was injured in Game 3 of the First Round of the 2017 playoffs against the Pittsburgh Penguins when a puck on a shot from Phil Kessel rode up the shaft of his stick and hit him in the face. He received stitches and a black eye but returned to the game in the third period only to leave again when his eye closed over. He was not able to play for the remainder of the playoffs.
Werenski was voted third in the Calder Memorial Trophy voting, an award given annually to the best rookie in the league. The award eventually went to Toronto Maple Leafs Auston Matthews.
On January 26, 2018, Werenski was called to replace fellow defensemen Seth Jones at the 2018 NHL All-Star Game. At the conclusion of the season, Werenski tied with Jones for most goals by a Blue Jackets defensemen in a season, with 16. After the Blue Jackets were eliminated from the 2018 Stanley Cup playoffs, Werenski revealed he had been playing with an undisclosed shoulder injury that had never healed in October. During the post season, Werenski had surgery on his shoulder and was expected to miss 5–6 months.
On September 9, 2019, the Blue Jackets signed Werenski to a three-year, $15 million contract extension.
On December 31, 2019, Werenski scored a hat-trick in a 4–1 Blue Jackets' win over the Florida Panthers and former goaltender teammate, Sergei Bobrovsky. Werenski finished the shortened 2019–20 season leading the league in goals by defensemen with 20.
On April 9, 2021, Werenski was ruled out for the remainder of the 2020–21 season due to a sports hernia.