Both players will play the 2019 season on $3.095 million deals.
A rotational tackle, Pierce averaged around 24 defensive plays per game for Baltimore in 2018, recording 32 tackles, four for loss and two QB hits. Since joining the Ravens as a UDFA in 2016, Pierce has missed just two games.
Onwuasor also joined the Ravens as a UDFA in 2016 and has established himself as a starting linebacker for Baltimore over the last two seasons. In 2018, Onwuasor averaged 25.4 plays per game, recorded a career-high 5.5 sacks and earned Defensive Player of the Week honors in Week 16.