The Ultimate Fighter 16 Finale’s Matt Mitrione was so concerned about being the best he could possibly be for Roy Nelson, he did something unusual for him: shut off Twitter.

An invitation to enroll with the Voluntary Anti-Doping Association, which was issued by Nelson more than a week ago, seemed like an unnecessary diversion, he said, though he’s not opposed to drug testing.

“Since I was coming on somewhat short notice, cutting a couple weeks out of my camp, and training for a five-round fight, this is something I wanted to make sure I didn’t have any thing that could distract me,” Mitrione told MMAjunkie.com (www.mmajunkie.com).

Mitrione (5-1 MMA, 5-1 UFC) vs. Nelson (17-7 MMA, 4-3 UFC) headlines The Ultimate Fighter 16 Finale, which takes place Saturday at The Joint at Hard Rock Hotel and Casino in Las Vegas. The event’s main card airs live on FX following prelims on FUEL TV and Facebook.

Mitrione, whose Twitter followers exceed 46,000, went on lockdown after agreeing to vacate a Dec. 29 fight with Phil De Fries at UFC 155 when Shane Carwin withdrew from the Dec. 15 event due to a knee injury.

It’s been almost 14 months since Mitrione last stepped into the cage, when at UFC 137 he was outpointed by Cheick Kongo in his first professional loss. He had beaten five consecutive opponents before the setback.

Mitrione caught flack from UFC President Dana White in September when he turned down a fight with Strikeforce heavyweight grand prix champ Daniel Cormier at an ill-fated Nov. 3 event, but said his decision to fill in for Carwin had nothing to do with the run-in.

Mitrione in March joined the Blackzilians team in Delray Beach, Fla., after stints working with Duke Roufus and fighters near his home in Indianapolis. He was originally scheduled to fight Rob Broughton in August at UFC on FOX 4, but Broughton was forced to withdraw.

“I brought my good credit rating, and now I’m official,” Mitrione said.

The Nelson booking hastened his preparation time.

“I know I had to cut a couple of weeks out of my training camp, so I had to make sure I was pretty active,” he said.

His decision, meanwhile, came as a let down to Nelson, who enrolled with VADA despite Carwin’s decision not to do the same.

“So far, I’m 0-2,” he said.

VADA conducts random drug screens of enrolled athletes and utilizes tests not traditionally performed by most state athletic commissions, including carbon isotope radio (CIR) testing and screens for human growth hormone and erythropoietin (EPO). It costs several thousand dollars to enroll, however, the group previously has offered sponsorships to fighters, including Nelson.

“Obviously, it isn’t ideal to have someone begin a program this late,” wrote VADA President Margaret Goodman in an email. “So, in my mind … although not ideal, it would serve a purpose.”

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