Kurt Busch
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After being forced to miss the past three NASCAR Cup Series races, Kurt Busch announced Wednesday afternoon that he has once again not been medically cleared to return to competition and will miss his fourth straight race this week at Richmond Raceway. Ty Gibbs will continue in his role as Busch's substitute driver behind the wheel of the No. 45 Toyota for 23XI Racing. 

After a hard crash in Turn 3 during the final round of qualifying at Pocono, Busch announced the following morning that he had not been medically cleared to race by NASCAR after suffering from "concussion-like" symptoms. Busch shared that he has still not been cleared this week despite feeling well outside of a simulated race environment.

"Brain injury recovery doesn't always take a linear path," read a statement by Busch. "I've been feeling well in my recovery, but this week I pushed to get my heart rate and body in a race simulation type environment, and it's clear I'm not ready to be back in the race car.

"This was by far the hardest week emotionally because I do feel the progression of recovery, but racing requires an extreme physical and mental effort, and my body is not 100% able to sustain the intense race conditions."

Gibbs, the 19-year-old grandson of Joe Gibbs and a championship contender in the NASCAR Xfinity Series, has driven Busch's car since Pocono and finished 10th this past weekend at Michigan. This is now the most races that Busch has ever missed in a single season -- he missed the final two races of 2005 after being suspended by Roush Racing following a DUI, was suspended one race in 2012 for violating probation, and was suspended for the first three races of 2015 after being accused of domestic violence by an ex-girlfriend.

After his injury put him out of commission at Pocono, Busch was granted a medical waiver by NASCAR that will allow him to qualify for the NASCAR Playoffs despite missing multiple races. Although Busch will be able to retain his playoff spot as long as he is able to return by the playoff opener at Darlington, whether he would remain playoff eligible if he has to miss a playoff race remains to be seen.

Busch moved onto the playoff grid by winning at Kansas in May, and he was 14th in points with one victory, five top fives and eight top 10s prior to his injury.