Pinion played college football at Clemson from 2012 to 2014 under head coachDabo Swinney. As a freshman in the 2012 season, Pinion only appeared in five games with teammate Spencer Benton doing a majority of the work that season. On September 8, he made his collegiate debut in the 52–27 win over Ball State. In the game, he had three punts for 117 net yards. Overall, in the 2012 season, he recorded nine punts for 355 net yards. As a sophomore in the 2013 season, Pinion became the main punter for the Tigers. That season, he handled the punting duties for all but three attempts, which went to Ammon Lakip and Andy Teasdall. In the season opener, against the Georgia Bulldogs, Pinion had a season-high seven punts for a season-high 287 net yards. In the next game, against South Carolina State, he had four punts for 195 net yards for a season-high 48.8 average. Overall, in the 2013 season, he had 56 punts for 2,205 net yards for a 39.4 average. As a junior in the 2014 season, Pinion continued his role as the main punter for the Tigers. That season, he handled all but one punt, which went to Andy Teasdall. He attempted and converted three extra points on the season. In the season opener, against the Georgia Bulldogs, Pinion had a season-high ten punts for a season-high 451 net yards. In two consecutive games in October, against Louisville and Boston College, he recorded games with 10 punts in each contest with 419 and 418 net punting yards respectively. On November 6, against Wake Forest, he recorded three punts for 147 net yards for a season-high 49.0 average. In his final collegiate game, against the Oklahoma Sooners in the Russell Athletic Bowl, he recorded five punts for 217 net yards. Throughout his junior season, teammates referred to Pinion as "the steering column" for his remarkable control over the direction of his punts. Pinion elected to forego his senior season and decided to enter the NFL Draft.
Pinion was drafted by the San Francisco 49ers in the fifth round, 165th overall, of the 2015 NFL Draft. He was the only punter to be selected in the draft that year.
2015 season: Rookie year
In the season opener against the Minnesota Vikings, Pinion had three punts for 140 net yards in his NFL debut. In Week 9, against the Atlanta Falcons, he recorded five punts for 241 net yards for a season-high 48.20 average. In Week 13, against the Chicago Bears, he recorded 9 punts for a season-high 433 net yards. Pinion recorded 91 punts for 3,969 net yards for a 43.62 average in his rookie season.
2016 season
Pinion began his second NFL season with very similar statistics in the first 3 games. In the season opener, against the Los Angeles Rams, he recorded seven punts for 319 net yards. In the next game, he recorded 7 punts for 318 net yards against the Carolina Panthers. During Week 3 against the Seattle Seahawks, he recorded 7 punts for 319 net yards. In Week 5, against the Arizona Cardinals, he recorded 7 punts for 349 net yards for a season-high 49.86 average. In Week 16, in the second divisional game against the Rams, Pinion recorded a season-high 9 punts for a season-high 372 net yards. Pinion recorded 100 punts for 4,402 net yards for a 44.02 average in 2016. His 100 punts led the league in punting.
2017 season
Pinion remained as the 49ers' punter going into his third professional season. In Week 4, against the Arizona Cardinals, he recorded seven punts for 351 net yards for a season-high 50.14 average. In Week 8, against the Philadelphia Eagles, he recorded eight punts for a season-high 364 net yards. In Week 12, against the Seattle Seahawks, he recorded a season-high nine punts for 342 net yards. Pinion recorded a then career-low 75 punts for 3,255 net yards for a 43.4 average in 2017.
2018 season
During the season opener against the Minnesota Vikings, Pinion recorded four punts for 174 yards. In Week 9, against the Oakland Raiders, Pinion recorded three punts for 164 net yards for a 54.7 average, including a season-long 64-yard punt. His performance against the Raiders earned him NFC Special TeamsPlayer of the Week. Pinion recorded a career-low 68 punts for 2,973 net yards for a 43.7 average in 2018.
