He has previously played in the NFL for the New Orleans Saints, Los Angeles Chargers, and the Buffalo Bills.

[6] After the season, he announced he was going to forgo his final year of eligibility and enter the 2018 NFL draft.

[11] He made his NFL debut on December 17, 2018, against the Carolina Panthers as a substitute for Michael Ola.

[14][15] Clapp spent much of the remainder of the 2020 season alternating between the active roster and the practice squad,[16][17][18][19][20][21][22][23] playing in several games in the middle of the season before being permanently added back to the active roster,[24] though he also spent time on the reserve/COVID-19 list during the postseason.

[13][23] Clapp started three games in 2021, playing with the likes of Jameis Winston, Trevor Siemian, and Taysom Hill after spending his first three years with Drew Brees under center.

[30] Following a season-ending health issue from starter Corey Linsley, Clapp was named the starting center in Week 4.