Ashton Sylve vs Joseph Diaz Jr. Preview June 20th, 2026
Former IBF Junior Lightweight Champion Joseph ‘JoJo’ Diaz Jr of South El Monte, California is back in the ring this Friday, June 19th when he takes on Ashton Sylve of Long Beach, California. The 10-round junior welterweight fight from Sylve’s hometown can be seen live in most nations on DAZN. Diaz last saw action in March when he dropped a unanimous 10-round decision to Alexis Rocha for his second straight defeat. In his previous outing in August, Diaz lost to former world champion Regis Prograis via a controversial 10-round unanimous decision. Diaz has now lost eight of his last 10 fights and has won just three of his past 12. Sylve last saw ring action in April when he beat Raul Hernandez by an eight-round unanimous nod.
Sylve vs Diaz Jr. Betting Odds
Here are the betting odds from online sportsbook BetOnline.ag (full review here).
- Joseph Diaz Jr. +483
- Ashton Sylve -800
My Pick
The 22-year-old Sylve enters the ring with an impressive record of 13-1 with 10 Ko’s and has 57 rounds of pro experience under his belt since making his debut in 2020. As an amateur, he won the 2016 USA Junior Olympics Final in the 101 lb Bantam Division and was reportedly a 10-time national champion. Sylve stands 5-feet-8-inches tall with a 68-inch inch reach and carries pretty good power in his fists as 77 per cent of his wins have come by stoppage but he has halted just one of his last four opponents.
The lone defeat on Sylve’s record came at the hands of Lucas Bahdi via a sixth-round knockout in July, 2024 with Sylve ahead by scores of 50-45 on all three of the judge’s cards. He bounced back from the loss with a fifth-round TKO over Daniel Lugo 16 months later and then beat Raul Hernandez by eight-round unanimous decision in his last contest in April. Sylve will be taking a step up in class against Diaz this weekend even though just three of his first 14 opponents entered the ring with a losing record.
As for Diaz Jr., he’s now 33 years old. He lost his first world title shot when he dropped a unanimous decision to WBC Featherweight Champion Gary Russell Jr. in 2018. He then beat WBA Titleholder Jesus Rojas by unanimous decision three months later but came in overweight for the fight and wasn’t able to win the belt. It was third time lucky for him though when he beat Tevin Farmer for the IBF Super Featherweight Title via unanimous decision in 2020.
He lost that belt when he failed to make weight against Shavkatdzhon Rakhimov in 2021 and ended up fighting to a 12-round draw with him. In his following fight he won the WBC interim belt with a unanimous decision over Javier Fortuna but lost it against Devin Haney and was then beaten by William Zepeda and Mercito Gesta before rebounding with a win over Jerry Perez and a defeat to Jesus Antonio Campos. That was followed by losses to Oscar Duarte by ninth-round stoppage, and a 10-round split decision to Abraham Montoya. He then bounced back with the decision over Jose Diaz before losing to Prograis.
All of this action brings Diaz’s pro record to 34-9-1 with 15 Ko’s and he’s just 1-5 in his last six outings. As an amateur, Diaz was a member of the U.S. Olympic Boxing Team at the 2012 Games in London, England where he went 1-1 as a bantamweight. He also reached the quarterfinals of the 2011 World Amateur Championships. He turned pro in 2012 and has fought 352 rounds since. Diaz has average power at best in his fists with 44.1 per cent of his wins coming by way of stoppage. He hasn’t recorded a knockout since halting Freddy Fonseca in 2019, which was 15 fights ago.
Diaz measures 5-feet-6-inches tall with a 64-inch reach so gives up two inches in height to Sylve as well as four inches in reach. He has also captured the NABF and WBO-NABO Featherweight Titles and the WBA Gold Super Featherweight Crown as a pro and has wins over Jesus Cuadro, Victor Terrazas, Rafael Rivera, Manuel Avila, Horacio Garcia, Jayson Velez, Hugo Partida, Rene Alvarado, Roberto Castaneda and Ruben Tamayo. He’s got a solid chin as he’s been stopped just once in 44 fights.
Prediction…
Diaz is 10 years older than Sylve and gives up size and power but he’s a tough son of a gun and always seems to make his fights quite entertaining. However his career is on the downslide with just three victories in his past dozen contests. Sylve is a very fluid boxer and he’ll have to work for it, but I’m expecting him to come out with a victory in his toughest test to date.
Sylve’s, size, power and skills should be the difference.
Play: Sylve -800 @ BetOnline.ag
Check out my recent boxing betting picks to see my current form.
Ashton Sylve betting • Joseph Diaz Jr. betting