Adreian Payne would have been the biggest star of Michigan State's deep March Madness run, had it not been for Lacey Holsworth. Instead, the 8-year-old cancer patient and passionate Spartans fan with whom Payne struck up an unlikely, but beautiful, friendship became the most heartwarming story of this year's college-basketball postseason.

Holsworth battled her disease just long enough to watch Payne — the man she called "Superman" and a "brother" — lead Michigan State to the NCAA tournament quarterfinals, where they lost to UConn on March 30. Earlier in the season, Holsworth had helped Payne cut down the nets after winning the Big Ten Conference tournament, and walked him out on the floor before his last home game for the Spartans — an honor typically reserved for close family members.

On Wednesday — less than 24 hours after the Holsworth family used social media to announce Lacey's death from a rare form of nerve cancer — Payne took to Twitter to pay a touching tribute to the girl who was one of his smallest fans, but undoubtedly his biggest supporter.

Payne, a rugged and skilled forward sure to be selected in June's NBA Draft, posted this message and photo from senior night to Twitter on Wednesday evening:

It was time for my lil princess to go home & feel no more pain,now she's happy & she's my angel watching over me. pic.twitter.com/bpUPCipcif

— Adreian Payne (@Adreian_Payne) April 10, 2014

That tweet was followed by this one two minutes later:

More dunks and 3s will be coming soon.!!! #RIPLacey pic.twitter.com/0HoXgsinZI

— Adreian Payne (@Adreian_Payne) April 10, 2014

Earlier Wednesday, Payne posted this photo to Instagram with a caption reading: "My Lil princess Lacey is an angel from god that will now watch over me. For ever and ever.#RIPLACEY"

Payne first met Lacey two years ago when the Michigan State basketball team visited a local hospital. Sports teams visiting hospitalized kids are a routine thing, but Payne and Lacey clicked in an uncommon way, according to the Detroit Free Press. Payne was moved by her optimism and upbeat personality despite being seriously ill, and the two used social media and text messages to keep in touch. Payne also continued to visit Lacey and her family in person, and the Holsworths became a common sight at the Breslin Center, Michigan State's home arena.

After Lacey's death, the Holsworth family posted this photo on Instagram, with a caption reading: "Princess Lacey has achieved the ultimate victory. She now dances among angels.... The world is a better place because you were in it. Our hearts are broken. We love you Doll. Dance all night..."

Payne and Lacey's friendship became the social web's hottest March Madness story this year. Other Michigan State players and Spartans coach Tom Izzo threw their public support behind her. National fans, media and players alike became touched by the friendship. Indeed, the name "Lacey Holsworth" was searched on Google more than 100,000 times on Wednesday after news broke of her death.

A crowdfunding effort to raise money for Lacey's treatment began after her story became a national sensation in mid-March. It's since received more than $89,000 in donations, which continue to pour in from supporters contributing money in her memory.

“She calls me her ‘Superman,’ but she’s the one who’s got the super strength,” Payne told the Free Press in March. “She’s incredible with everything she’s gone through. [Doctors) told her she wouldn’t walk again. But she did. She’s just an incredible fighter. And if I can bring her a little bit of happiness to help her forget everything for a little while, then that’s what I want to do.”

If you want to learn more about Lacey and Payne's touching friendship, this video from March 9 tells the story well: