Nick Viall is going to be faced with a lot of tough decisions during Season 21 of “The Bachelor” — which girls will he keep, which will he send home and how will he face a previous one-night-stand, for example.

Us Weekly broke the news that someone from Nick’s past had been cast in the upcoming season of the popular ABC dating series. Sources said “The Bachelor” star and the mystery contestant — identified by Reality Steve as Elizabeth Sandoz — met at a wedding during which they had a very brief fling. Us reported that neither acknowledged their previous connection during “The Bachelor” filming. While it has yet to be brought up, it seems it may create problems down the line, as another insider claims the Milwaukee, Wisconsin, native was adamant that he did not want anyone from his past cast on the show. In fact, he is said to have called it “a waste.”

“During the first day of taping all the girls came out, and he actually had slept with one of them at a wedding and never called her again,” one source told Us.

Craving more details about Elizabeth and her seemingly juicy ties to Nick ahead of the new season of “The Bachelor”? Reality Steve did a little digging, uncovering details from her past as well as potential leads on when and where the pair hooked up. The Season 21 “Bachelor” contestant is 29 and hails from Nebraska, according to the blog. She currently lives in Las Vegas and is close with former contesant Jade Roper. Elizabeth was a member of Jade’s wedding party, standing beside her as she and Tanner Tolbert said their “I Dos” in a televised special. Nick was also present during Jade and Tanner’s wedding, which Reality Steve speculates is when their rumored one night stand took place. While Us’ sources claim that Nick and Elizabeth’s past had not yet come up, the blog suggests that the contestant will bring it up at some point to another “Bachelor” hopeful.

Stories began circulating about Nick and Elizabeth — along with the many other women he’s courting on this season of “The Bachelor” — after they were seen filming dates and other activities for the show. On Oct. 8, Nick was spotted on a one-on-one date with contestant Raven Gates at Skateland in Waukesha, Wisconsin. Photos and videos were shared from their outing on Twitter by Reality Steve and producer Mike Fleiss. Prior to their skate date, Nick and Raven attended a youth soccer game for his younger sister.

Days prior, Nick was seen on a date with contestant Danielle Lo at the Pabst Theater in Milwaukee. He is also said to have organized a group date at a dairy farm, followed by an after party at the Paine Art Center and Gardens in Oshkosh, Wisconsin.

Nick has been spotted out and about with his potential love interests on numerous occasions in Wisconsin. On Sept. 13 filming for “The Bachelor” began. At the time, Reality Steve reported that Nick was shooting his intro video for the show. He was also seen strolling around at the Riverwalk in downtown Waukesha, and is said to have visited the town’s “best coffee shop,” The Steaming Cup. Photos of Nick were posted on Facebook by the local library.

Most recently, Nick was seen shooting scenes for the show in New Orleans. “The Bachelor’ Season 21 will premiere in 2017. An exact date has yet to be announced.

“The Bachelor” “The Bachelor” contestant Nick Viall will reportedly come face-to-face with a former fling during Season 21 of the ABC dating show. Photo: ABC