He played college football for the Wisconsin Badgers, and was selected by the 49ers in the third round of the 2014 NFL draft.

[1] Borland attended Archbishop Alter High School in Kettering, Ohio, where he was first-team All-state and All-conference player of the year.

He was the runner-up to the state title in the shot put event at the 2009 OHSAA District T&F Championships, recording a career-best throw of 18.62 metres (61.1 ft).

He was also listed on the preseason watchlists for All-Big Ten, first-team by Phil Steele and second-team by Athlon.

[5] Borland set a season high with 13 tackles in the 2012 Big Ten Football Championship Game against Nebraska.

Following the season, Borland was named first-team All-Big Ten by the coaches and honorable mention by the media.

[12][13][14] Throughout training camp and preseason, he competed against 49ers veteran Michael Wilhoite for a starting inside linebacker position left absent by the injured NaVorro Bowman.

[15] In the last preseason game against the Houston Texans, Borland led the defense in tackles with six and returned an interception 34 yards for a touchdown.

[19][20] In a week 10 matchup against the New Orleans Saints, Borland recovered an overtime fumble that led the 49ers to a 27–24 victory.

He has received both praise and criticism for his assertions in many interviews, including one with CBS News in which he stated that he believes football as a whole to be "inherently dangerous".

Borland appeared in Episode 2 & 3 of the Netflix special three-part docuseries, Killer Inside: The Mind of Aaron Hernandez and discussed brain health in relation to football.

After ESPN called him “the most dangerous man in football” for discussing the problem with concussions, he said that “I fell into a funk.

It was a hard couple of months.”[33] In the same interview he said he works with the After the Impact Fund, which is a non-profit focused on helping veterans with PTSD and athletes with concussions.