Justin Gaethje recently received an unexpected opportunity and plans on taking full advantage of it. Less than two weeks after being chosen as a replacement for Khabib Nurmagomedov, Gaethje will battle Tony Ferguson for the interim lightweight title in the main event of UFC 249 on Saturday, April 18. The main UFC 249 fight card is scheduled to start at 10 p.m. ET from an undisclosed location. Gaethje (21-2) owns a 6-0 career record in title fights, all of which took place from 2014 to 2016 during his tenure with the World Series of Fighting.

Gaethje presents a unique challenge for Ferguson (26-3), who had been preparing to face Nurmagomedov before the current UFC lightweight champion was replaced because of travel restrictions stemming from the coronavirus pandemic. Ferguson is aiming for his 13th straight victory as he fights for the interim title for the second time in his career. The accomplished grappler is a -200 favorite (risk $200 to win $100), while Gaethje is a +170 underdog in the latest Ferguson vs. Gaethje odds from William Hill. Before making your UFC 249 picks, make sure you see what SportsLine MMA expert Kyle Marley has to say.

Marley won the first-ever "ToutMaster" UFC betting contest sponsored by MMAOddsBreaker and also appears regularly on multiple MMA betting and DFS shows. Over the past year, $100 bettors who have followed Marley's picks are up nearly $19,000.

While posting an amazing 8-3 record last month at UFC 248, Marley told SportsLine members to expect middleweight champion Israel Adesanya (-275) to retain his title against Yoel Romero (+235) by unanimous decision. He argued that Adesanya would pick Romero apart while on his feet and was proven correct as the champ dominated the action with leg kicks. Anyone who has consistently followed Marley is way up,

Now, with UFC 249 fast approaching, Marley has carefully studied every matchup on the card, identified the best value in the UFC odds and released his MMA picks for every single fight. He's only sharing those selections here

Ferguson vs. Gaethje preview

Marley knows Ferguson had been preparing to fight Nurmagomedov, who is stuck in Russia. It marks the fifth time a matchup between the two has failed to take place after being booked.

Ferguson is in the midst of the longest winning streak in UFC lightweight history. The 36-year-old Californian has won 12 consecutive fights, the last being a second-round TKO against Donald Cerrone on June 8.

A former collegiate wrestling champion, Ferguson has not lost since dropping a unanimous decision to Michael Johnson on May 5, 2012. He captured the interim lightweight championship with a submission win over Kevin Lee in October 2017, but was stripped of the title after withdrawing from a fight with Nuragomedov in April 2018 due to a torn knee ligament.

Ferguson's winning streak could come to an end against the fourth-ranked Gaethje, who has recorded three straight victories after suffering back-to-back losses. The 31-year-old from Arizona's most recent win also came against Cerrone, as he scored a TKO in the first round on Sept. 14. You can see Marley's full Ferguson vs. Gaethje picks here.

Top UFC 249 predictions

We'll share one of Marley's UFC 249 predictions here: He's backing Yorgan De Castro (+165) to record an upset win over Greg Hardy (-195) in a heavyweight bout originally scheduled to headline last month's UFC Columbus card that was postponed. 

De Castro has yet to lose in his young Mixed Martial Arts career, winning his first six fights. The 33-year-old from the island nation of Cape Verde has recorded five of his victories by knockout, including a first-round TKO of Justin Tafa on Oct. 5 in his UFC debut.

A former Pro-Bowl defensive end for the Carolina Panthers who spent six seasons in the NFL, Hardy has gone 5-2 with one no contest since making his MMA debut in June 2018. The 31-year-old striker, who at 6-foot-5 has a five-inch height advantage over De Castro, is coming off a unanimous-decision loss to Alexander Volkov in November.

"This fight comes down to who lands the big punch, and at these odds, I would rather take the underdog," Marley told SportsLine.

How to make UFC 249 picks

Marley also has strong picks for Ferguson vs. Gaethje and every other bout on the UFC 249 card. He's also backing a fighter who's much more dangerous on the mat. Get every pick for every fight on the UFC 249 card at SportsLine.

Who wins Ferguson vs. Gaethje? And how exactly does each fight end? Visit SportsLine now to get detailed picks on every fight on the UFC 249 card, all from the accomplished expert who's up almost $19,000, and find out.

UFC 249 odds (via William Hill)

Tony Ferguson (-200) vs. Justin Gaethje (+170)
Greg Hardy (-195) vs. Yorgan De Castro (+165)
Vicente Luque (-250) vs. Niko Price (+190)
Calvin Kattar (-270) vs. Jeremy Stephens (+220)
Francis Ngannou (-310) vs. Jairzinho Rozenstruik (+250)
Jacare Souza (-150) vs. Uriah Hall (+125)
Alexander Hernandez (-230) vs. Omar Morales (+190)
Ray Borg (-125) vs. Marlon Vera (+105)
Michael Johnson (-230) vs. Khama Worthy (+190)
Sijara Eubanks (-330) vs. Sarah Moras (+260)
Ryan Spann (-330) vs. Sam Alvey (+260)