He played college football for the Notre Dame Fighting Irish and was signed by the Green Bay Packers as an undrafted free agent in 2008, but never appeared for the team.

He attended Rancho Solano Private School prior to that, where he starred as quarterback, leading the RSPS Mustangs to an MVAL championship in 1999.

[3] The Packers traded Jansen to the Carolina Panthers for a conditional pick in the 2011 NFL draft on April 13, 2009.

[10] On November 27, 2022, Jansen tied former longtime Panthers kicker John Kasay for most games played for the franchise (221).

[12][13] After playing in all 17 games for Carolina during the 2024 season, Jansen re-signed with the team on a one-year contract on February 14, 2025.