[2] Connaughton attended St. John's Preparatory School in Danvers, Massachusetts, where he starred in three sports, playing quarterback in football and multiple positions in both baseball and basketball.

He suddenly emerged as a major basketball prospect after what ESPN.com writer Jeff Goodman called "one spectacular week" at the Amateur Athletic Union national tournament in Orlando, Florida, including a game where he had 33 points and 20 rebounds.

[4] As a pitcher for the baseball team, he had an 11–2 win–loss record with a 1.75 earned run average (ERA) and 160 strikeouts in 90 innings pitched as a senior.

The Fighting Irish appeared in the 2012 NCAA Men's Division I Basketball Tournament, but lost to Xavier University in the second round.

[3][11] After his junior year, he was forthright about his intent to return to Notre Dame for his senior basketball season, despite warnings that it would impact his prospects for the upcoming baseball draft.

[12] He took part in a 2015 tournament game against Kentucky for a Final Four berth, narrowly lost by his team after having sustained a lead until the six-second mark.

Connaughton was determined to finish his degree at Notre Dame, and had a 3.0 grade point average with the university's Mendoza College of Business.

Connaughton made his professional baseball debut with the Aberdeen IronBirds of the Class A-Short Season New York–Penn League, in which he registered a 96 miles per hour (154 km/h) fastball.

As a result, the ballclub continued to control his contractual baseball rights through 2020, which could have been extended for six additional years if Baltimore placed him on its major league roster.

[18] The Orioles did not add him to their major league roster in that span, meaning Connaughton would be free to sign with any team if he decided to return to baseball.

[24] In the Trail Blazers' 2017–18 season opener on October 18, 2017, Connaughton scored a career-high 24 points while making 4 of 6 3-pointers in a 124–76 win over the Phoenix Suns.

[27] On August 20, 2020, Connaughton scored 15 points and grabbed 11 rebounds in a 111–96 Game 2 win during the Bucks' first round postseason matchup against the Orlando Magic.

[31] On April 27, during the first round of the 2022 NBA Playoffs, Connaughton scored 20 points in just 23 minutes of playing time in a decisive 116–100 Game 5 win over the Chicago Bulls.

"[3] Notre Dame head basketball coach Mike Brey added, "In my 15 years here, no one has been more responsible than Pat Connaughton.

In March 2020, Connaughton and the firm drew criticism for razing a historic building to make way for a new apartment complex in Milwaukee.