Taylor Swift and Katy Perry avoided one another like the plague during a post Grammy's party Sunday night, with the "By the Grace of God" singer making certain to leave one event just before her nemesis was scheduled to arrive.

According to HollywoodLife.com, the two pop-divas have not been able to put their long list of disrespectful comments about one another behind them and now appear intent on simply staying out of each other's lanes.

"Word was that Taylor was meant to show up, and Katy left before any of that could happen," a source told the website of the Universal Music Grammy Party sponsored by American Airlines and Citi. "Taylor didn't show because rumors were that she knew Katy was there, and Katy left thinking Taylor was going to show, so they definitely made an effort to avoid each other."

The longtime rivals' beef was awakened anew this month when Perry used her Super Bowl halftime performance to apparently mock Swift by having her dancers dress in a bikini outfit similar to the one Swift was once known to wear.

Since then, Perry's boyfriend John Mayer used his "Late, Late Show" temporary hosting gig to also slam the 25-year-old Swift, telling the audience, "you can see me at the Grammys doing what I do best, being avoided by Taylor Swift. That won't make the internet at all."

Swift and Mayer dated for a while in 2009 and her "Dear John" song is notoriously thought to be about him.

Other than their apprehensions about one another, both Perry and Swift appeared to have memorable evenings. The 29-year-old Perry performed her "By the Grace of God" tune during the show to rave reviews and after six-years Swift seemed to finally put her once simmering beef with Kanye West behind her by mugging for pictures with him.