Brock Lesnar UFC WWE
Brock Lesnar prepares to fight Mark Hunt during UFC 200 at T-Mobile Arena on July 9, 2016 in Las Vegas. Rey Del Rio/Getty Images)

Brock Lesnar didn’t appear on the latest episode of “Monday Night Raw,” even though he was advertised to have an in-person confrontation with Roman Reigns. He wasn’t at WWE’s Elimination Chamber pay-per-view in Las Vegas Sunday when Reigns earned a title match for Lesnar’s WWE Universal Championship at WrestleMania 34.

Lesnar was in Las Vegas this past weekend, only he didn’t choose to spend it with WWE. He, instead, spent time with Dana White, as evidenced by the picture shared by the UFC president on social media.

All it took was one Twitter post to fuel speculation about Lesnar’s future.

The former UFC heavyweight champion has flirted with leaving WWE for a return to MMA before. He competed at UFC 200 in 2016, though he did so while under contract with WWE and took part in the main event of SummerSlam just one month later. The partnership between WWE and UFC might have continued—Lesnar soundly defeated Mark Hunt by unanimous decision—but Lesnar was handed a one-year suspension after testing positive for performance-enhancing drugs.

WrestleMania 34 is just 40 days away, and Lesnar is in almost the same position he found himself in three years ago. He was about to headline WrestleMania in a title match with Reigns, and his WWE contract was set to expire shortly after the PPV.

Just a few days before WrestleMania 31, Lesnar announced that he was re-signing with WWE. He lost the WWE Championship at the PPV, but has since gone on to win the Universal Championship, headlining several shows along the way.

Lesnar might ultimately decide to stick with WWE again. He’d have to re-enter the USADA drug-testing pool and serve the final six months of his suspension before he could have another UFC fight.

Leaving WWE, with whom Lesnar has been under contract since 2012, seemed to be a more likely option last summer. That’s when talk of a super-fight between Lesnar and former UFC light heavyweight champion Jon Jones reached its peak.

A second failed test for performance-enhancing drugs by Jones could prevent that bout from ever happening. Jones faces a multi-year suspension, and Lesnar will turn 41 years old this summer.

That doesn’t mean Lesnar won’t at least flirt with the idea of going back to the UFC. It gives him even more leverage in negotiations with WWE, where he already works on a part-time schedule.

No matter what Lesnar’s future holds, don’t be surprised if WWE uses the idea that Lesnar could jump to the UFC as part of the WrestleMania storyline.

It’s unclear why Lesnar didn’t appear on “Monday Night Raw.” Whether it was planned or not—there’s little chance the champion simply decided to not show up—Reigns called out Lesnar for not caring enough about WWE to make the event.

Expect Paul Heyman, Lesnar’s mouthpiece, to make reference to the possibility of his client jumping ship to the UFC in April. The threat of Lesnar retaining the belt and taking it to another company could create even more buzz surrounding WWE’s biggest match of the year.