On the heels of his upcoming interim title shot, UFC middleweight Yoel Romero will be looking for some restitution from a supplement maker.

In early 2016, Romero was suspended for six months by USADA after he tested positive for the banned substance Ibutamoren following a split-decision win over Ronaldo Souza. Romero claimed that supplement was tainted, and when USADA tested a separate independent sample of the supplement in question, it found that to be the case.

Still, Romero was subject to the six-month ban. And now, two years after he first was informed of the violation, he is suing the supplement maker, Goldstar Performance Products, according to a report from Forbes.

Romero filed the suit in New Jersey Superior Court, the report said, in regards to the company’s Shred RX product, which Romero said he was using when he tested positive in December 2015 a few days after his win over Souza.

Romero, the complaint says, gave USADA a Shred RX capsule from the bottle he had been taking from, and it tested positive for Ibutamoren. When USADA purchased a separate bottle of the product for an additional test it, too, tested for Ibutamoren. That led USADA to reach the determination that Romero had taken a tainted supplement, since Ibutamoren was not listed as one of the Shred RX ingredients, and it caused his suspension to be only six months.

According to the report, Romero’s complaint in the suit says Goldstar Performance Products “failed to maintain the production facility,” and also that it knew the supplement was contaminated. This, the complain says, damaged his reputation and caused him to lose a shot at the middleweight title.

This past July, Romero (12-2 MMA, 8-1 UFC) suffered his first loss in the UFC when he dropped a decision to Robert Whittaker (19-4 MMA, 10-2 UFC) in an interim middleweight title fight at UFC 213. Whittaker went on to become the middleweight champ with the removal of the interim tag when Georges St-Pierre vacated the belt he won from Michael Bisping.

Whittaker was supposed to fight former champ Luke Rockhold (16-3 MMA, 6-2 UFC) in the UFC 221 main event Feb. 10 at Perth Arena in Perth, Australia, on pay-per-view. But this past week, he was ruled ineligible due to injuries, and Romero was elevated to the fight with Rockhold for another interim belt, despite coming off a loss.

Romero had been booked to fight David Branch at UFC on FOX 28 on Feb. 24 at Amway Center in Orlando, Fla., but now will have another crack at a title. A win presumably would get him an eventual rematch with Whittaker in a title unification fight.

For more on UFC 221, check out the UFC Rumors section of the site.