'A true comedic genius': Mario Lopez, Mark-Paul Gosselaar more mourn Dustin Diamond

Celebrities are mourning the death of Dustin Diamond, who died Monday following his cancer battle.

Diamond, who died at 44 following his carcinoma diagnosis, was famed for playing the relatable, irritating geek Samuel "Screech" Powers from the late 1980s until 2000 on TV sitcom "Saved by the Bell." His Bayside High School classmates were among the first to pay tribute to the actor. 

"Dustin, you will be missed my man," Mario Lopez, who played A.C. Slater, tweeted. "The fragility of this life is something never to be taken for granted. Prayers for your family will continue on..."

Mark-Paul Gosselaar, who played Zack Morris, remembered Diamond as "a true comedic genius."

"My sincere condolences to his family and friends. Looking back at our time working together, I will miss those raw, brilliant sparks that only he was able to produce. A pie in your face, my comrade," he wrote.

"I am deeply saddened by I (sic) the news of my old co-star @realdustindiamond passing," Tiffani Thiessen, who played Kelly Kapowski, wrote on Instagram. "Life is extremely fragile and it’s something we should never take for granted. God speed Dustin.