Alexandra Grant Throttles Keanu Reeves

It’s the end of the road for Keanu Reeves’ racing career — if his fiancée, Alexandra Grant, has her way! After the Speed star, 60, narrowly avoided a crash during his professional racing debut on Oct. 5 at the Indianapolis Motor Speedway, sources say Grant threatened to hit the road if Keanu didn’t pull his race car into a permanent pit shop.

Alexandra, a 54-year-old artist, has been the actor’s constant companion for the past five years. “She’s indulged his racing up to now, even going to the track with him and waving. But this really scared her,” an insider says. “She told him in no uncertain terms — it’s the race cars or the end of the road for their relationship!”

Keanu escaped injury after his car spun into the grass as he exited a turn about halfway through the race.

“Alexandra loves Keanu deeply and doesn’t want to see anything like that happen to him again,” the source spills. “She told him if he tries to get back on the track, she’ll hurt him herself!”

But a rep denies an ultimatum was issued, saying Grant “supports Keanu in everything he wants to do.”

Reeves is no stranger to life-threatening accidents. When he was 23, he was riding his motorcycle when he wiped out on a hairpin turn in Los Angeles. At the hospital, doctors had to remove his spleen, leaving a long scar on his abdomen.