The Christmas game between the Baltimore Ravens and the Houston Texans sparked fireworks even before the game started.

According to ESPN’s Jamison Hensley, Texas running back Joe Mixon and Ravens backup quarterback Josh Johnson exchanged words at midfield during pregame warmups and had to be separated.

Steve Wyche took a look at video of the argument during the Netflix broadcast:

It’s not clear what may have caused the argument between Johnson and Mixon. Johnson is a journeyman who was a member of an NFL-record 14 different teams, but he didn’t come into contact with Mixon after the speedster entered the league as a second-round pick of the Cincinnati Bengals in 2017. Johnson played for the Bengals in 2013 and was on their practice squad in 2015.

Mixon is in his first year with the Texans after being acquired from the Bengals in an offseason trade. In 12 games this season, he rushed for 967 yards and 11 touchdowns on 231 carries, as well as 33 catches for 291 yards and another score.

Houston will be more reliant on Mixon than ever as its already depleted receiving corps suffered another blow when wideout Tank Dell suffered a devastating knee injury in Saturday’s loss to the Kansas City Chiefs, ruling him out for the remainder of the season. The Texans already lost star receiver Stefon Diggs to a torn cruciate ligament at the end of the season.

After the pregame altercation, Mixon may have a little more energy as he tries to lead Houston past Baltimore in a potential AFC playoff preview.