Image: Supplied.

Defending 250SX East champion Chase Sexton has undergone surgery after breaking his collarbone in a pit bike incident last weekend.

The Geico Honda entry, who was understood to be targeting an attack at the 250SX West championship, will now defend his crown on the east coast as a result.

Sexton has stated he’ll be sidelined for a three-week period, bringing his return to riding around the time of Anaheim’s Monster Energy Supercross season-opener on 4 January.

“Unfortunately I had a mishap on Sunday riding 110s that led me to break my collarbone,” Sexton said in a statement. “This feels like deja vu to last year, but I’ve already gotten surgery to fix it and we are on the mend now. Off the bike for three weeks and then back at it trying to defend the 1E this year.”

Sexton signed a unique deal for 2020 and beyond, which will see him race the 250SX East championship with Geico Honda before graduating to the premier class with Team Honda HRC for the Lucas Oil Pro Motocross Championship.