NFL week 1, US Open, Premier and Champions Leagues: weekend briefing

MetaMask Alpha is MetaMask's market digest. Context, data, signal—not financial advice.

NFL week 1, a US Open quarterfinal upset, the opening round of the Champions League, and a Premier League matchweek all land inside seven days.

NFL: a 20-point loss cost the Rams two points

The Los Angeles Rams lost 27-7 to the San Francisco 49ers on Thursday, September 10, in the NFL's first regular-season game in Australia. In the 2027 Champion market on Polymarket, the Rams priced at 16.5% at kickoff and 14.5% as of 6:00 pm ET on Friday, September 11—still the highest price in the field.

The 49ers gained more than the Rams gave up. San Francisco moved from 3.45% at kickoff to 6%, which places it sixth, behind the Rams (14.5%), Buffalo (8.5%), Seattle (7.5%), and Baltimore and Kansas City (both 6.25%). Seattle didn't move at all—7.5% before its opener and 7.5% after—despite beating New England 13-10 on Wednesday and losing quarterback Sam Darnold to a hip injury on the opening drive.

The market has traded more than $52 million since it opened in February, including about $2.2 million in the past week. MetaMask covered what the same market was pricing before kickoff on September 7, and what Polymarket is and how decentralized prediction markets work covers the mechanics underneath it.

US Open: an American guaranteed in the final; Zverev is the favorite

Ben Shelton beat defending champion Carlos Alcaraz in five sets in a quarterfinal that finished at 3:33 am on Wednesday, September 9—the latest finish in US Open history. Shelton priced at 7.15% in the tournament winner market on the evening of September 8, while the match was still on court. Two days later he was at 36.3%.

Shelton meets Frances Tiafoe in an all-American semifinal, which guarantees an American man in the final. No American man has won a major since Andy Roddick at the 2003 US Open. The draw also guarantees a first-time US Open champion: Jannik Sinner withdrew with a knee injury, Novak Djokovic lost in the first round, and Alcaraz is out.

After Alexander Zverev advanced to the finals on Friday, he priced at 59% to win it all. Zverev won the French Open in June and is the only one of the four with a major already. Roughly $2.5 million of the market's $25 million lifetime volume arrived in the past week. The final is Sunday, September 13, and the core terminology behind these prices is worth a read first.

Premier League: City favored at Old Trafford, and Spurs still haven't scored

Manchester United host Manchester City at Old Trafford on Sunday, September 13 at 4:30 pm BST. City price at 46.5%, United at 29.5%, and the draw at 24.5%. United arrive on the back of a 4-0 Champions League win over Sabah; City opened their European campaign with a 2-0 win at Porto.

Tottenham host Everton on Saturday, September 12. Spurs have one point and no goals from three league matches and sit 18th, while Everton are unbeaten. The market prices Tottenham at 47.5%, with Everton and the draw both at 26.5%.

Both single-match books are thin next to the season-long ones: the derby has traded about $43,000 and Tottenham–Everton about $23,000, against tens of millions on the futures markets. For how the season-long books are structured, see Premier League prediction markets explained.

Champions League: Barcelona prices ahead of the back-to-back champions

PSG retained the title in May, beating Arsenal on penalties to become the second club to go back-to-back in the Champions League era after Real Madrid in 2016–17. The 2027 Champion market has someone else in front. As of Friday, September 11, Barcelona priced at 18.5%, Bayern Munich at 15.5%, Arsenal at 14.5%, and PSG and Real Madrid at 12.5% each.

Barcelona gained two points across the opening round, from 16.5% on September 5. Arsenal slipped from 15.5% to 14.5% and PSG from 13.5% to 12.5%. About $7.5 million changed hands in the past week against $31.7 million in lifetime volume—close to a quarter of everything the market has ever traded, concentrated around the September 8–10 matchday.

Then it goes quiet. Matchday 2 isn't until October 13–14. MetaMask's Champions League prediction markets explained maps the full calendar from here to the final in Madrid on June 5, 2027.