William Shatner remembers Leonard Nimoy: 'I never had a friend like that'

William Shatner challenged ET's Brooke Anderson to an arm-wrestling competition in 2011, and on Monday it was time for a rematch.

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"I remember that was the first time a lady beat me," Shatner said of his competition with Brooke.

Brooke remembered it the other way around, so the two squared off again on the ET stage with Kevin Frazier officiating.

The 84-year-old actor's competitive spirit runs deep. His Hollywood Charity Horse Show starts this weekend to benefit local charities like A Place Called Home, Blind Children's Center, BraveHearts Therapeutic Riding & Educational Center, Children's Hospital Los Angeles and more.

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"[It benefits] many children's charities, veterans charities," Shatner said. "Every cent that comes into us goes out to the kids and to the veterans."

Shatner's late Star Trek co-star Leonard Nimoy also was a big supporter of charities, including the Nimoy Foundation, established in 2003 to support that work of artists through grants. In 2009, Nimoy gushed about Shatner, saying, "I consider him like a brother to me."

"I never had a friend like that," Shatner told ET. "It's a tough one to lose."

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Nimoy passed away in February due to the end stages of chronic obstructive pulmonary disease (CPOD). While Shatner didn't really get a chance to say goodbye to Nimoy, he revealed that their last correspondence was meaningful.

"I sent him an email at the very end, telling him to be happy," Shatner said. "That he was loved."

Nimoy's last tweets:

Stars react to Nimoy's death:

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