Christopher Bell has admitted that it will be a 'game-time decision' whether he runs the full length of Sunday's NASCAR Cup Series race at Coronado Naval Base.

The Joe Gibbs Racing star fractured his wrist just two weeks ago at Michigan, and admitted that he's still unsure whether he's going to be able to attempt all 75 laps around the 3.4-mile street circuit, or have to hand off to teenage reserve driver Brent Crews.

Bell was speaking after Friday's practice session, which he started out in the car before handing over to Crews for the youngster to pick up some potentially valuable experience.

Asked whether he'll make the race distance, he admitted: "That’s going to be a decision that we weigh out as it unfolds. So we haven’t made the decision yet, and yeah, I think it’s gonna be a game-time decision.”

READ MORE: 6 burning questions about this weekend's NASCAR races at Coronado Naval Base

Bell: San Diego is a high-risk racetrack

The 31-year-old claimed that the issue isn't so much one of pain tolerance, as much as it is one of not being able to be as 'quick and aggressive' on the steering wheel as he needs to be.

“Myself and Adam (Stevens, crew chief) are really going to have to sit down and talk about what our goals are,” he said. “I will say that it’s a very high-risk racetrack and I can't afford any setbacks. I'm already two weeks into this healing process now.”

The major risk to the still-healing bone would come from any contact where the steering wheel could snap in his hand, he explained. “Any sort of miscalculation on the apex, walls or wheel-to-wheel contact and the wheel jerks in my hand. Those are the kind of things that I think we're all worried about.”

Bell also confessed that last weekend's race at Pocono made him realise that he is going to be more affected by his injury than he realised, admitting he is 'not driving at a hundred percent'.

"Before Pocono," he said, "I thought I was going to be completely fine, and I thought that I was going to be able to drive the car completely fine, and Pocono was an eye opener of ‘I'm not at a hundred percent and I'm not driving at a hundred percent.’

“I'm not my normal self. So, with that being said, yeah, I was over-optimistic and I understand now that I'm not at a hundred percent.”

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