Although Paris Hilton and Doug Reinhardt have split, the two can't seem to avoid each other.

After both were spotted in Coachella, their paths crossed again last night in Hollywood at the grand opening of the Syndicate Group's MyStudio, where David Arquette, David Spade, Adam Levine and Samantha Ronson were also hanging out.

Doug was already inside when Paris arrived around 1 a.m. after dining with girlfriends at Boa.

"He was staring at her the whole time, but she didn't acknowledge him," a source tells E! News of the showdown. Luckily there was no drama between the exes, and Paris left the hot spot around 1:45 a.m. to go party with a more famous hottie...

After dancing up a storm at MyStudio, Paris and her girls went over to Trousdale, where she was spotted sharing a table and chatting with Leonardo DiCaprio and his entourage.

Leo was out solo with his guys, although he attended the Lakers game earlier that night with girlfriend Bar Refaeli.

As for whether there could be any romance brewing between newly single Paris and the perennial bachelor, a source simply tells me, "They've been friends for years."

Stay tuned!