[2] The Toronto Blue Jays selected McGuire in the first round of the 2010 Major League Baseball draft.

[4] He made his professional debut that season with the Dunedin Blue Jays of the Class A-Advanced Florida State League.

McGuire was promoted from Dunedin, after posting a 7–4 record with 102 strikeouts and a 2.75 earned run average (ERA) over 19 appearances and 104+2⁄3 innings pitched.

[7] On March 10, 2014, the Blue Jays optioned him to the Buffalo Bisons of the Class AAA International League.

[10] He was optioned to the Sacramento River Cats of the Class AAA Pacific Coast League (PCL).

On November 16, 2017, McGuire signed a minor league contract with an invitation to spring training with the Toronto Blue Jays.

On June 15, 2018, McGuire was claimed off waivers by the Texas Rangers and immediately optioned to Triple-A.

[27] On April 21, 2019, McGuire threw a no-hitter against the Hanwha Eagles, striking out 13 batters en route to a 16–0 win.

On March 31, 2022, McGuire signed with the Gastonia Honey Hunters of the Atlantic League of Professional Baseball.

[32] In 20 games (14 starts) for the Triple-A Louisville Bats, he posted a 4-5 record and 6.32 ERA with 60 strikeouts across 74 innings of work.

[34] On October 11, 2023, McGuire was hired by the Georgia Institute of Technology to serve as an undergraduate assistant coach.