The 2021 MLS All-Star Game kicks off tonight in Los Angeles (9:30pm ET, FS1 and Univision), and the stakes are higher than ever, with stars from MLS playing stars from Liga MX (Mexico).

Why it matters: Two leagues squaring off in an All-Star Game in the middle of their seasons is unprecedented. And these aren't any two leagues — MLS and Liga MX are regional rivals.

The backdrop: MLS has had numerous All-Star Game formats over the years. There was East vs. West, MLS USA vs. MLS World, MLS All-Stars vs. USMNT, and since 2005, the opposition has been top European clubs.

• Tonight's matchup could be the most competitive game yet, thanks to the longstanding soccer rivalry between the U.S. and Mexico.
• Reminder: The USMNT beat Mexico in the Nations League and Gold Cup finals this summer, so Liga MX is out for revenge.

What they're saying: "Some of the best sporting events I've ever been to are USA-Mexico matches," MLS commissioner Don Garber told me via phone. "If we can deliver a club version of that incredible rivalry, it's going to be great for our leagues and our fans."

• MLS, with 27 teams in the U.S. and Canada, and Liga MX, with 18 teams in Mexico, have competed in numerous competitions. But this week's festivities, which began with Tuesday's skills challenge, represent their most intimate collaboration.
• "Liga MX is looking to open up the commercial market here in the U.S., and MLS is looking to grow the connection with Mexican-American soccer fans," says Garber. "So we both have mutual goals that games like this help us achieve."

The big picture: Earlier this year, FIFA president Gianni Infantino said a merger between MLS and Liga MX could produce "the best league in the world." While Garber says there are no such plans, he's enthusiastic about broader cooperation between the two leagues.

• "My view is, there's no reason why CONCACAF (North America, Central America and Caribbean) in time can't be as important as CONMEBOL (South America), and even — in many, many years — as important as UEFA (Europe)."
• "We do things a little differently in this part of the world, but we have rabid fans and a robust commercial market. And a close association between MLS and Liga MX is going to help drive growth."

Go deeper: Top 10 players who appeared in both MLS and Liga MX (MLS.com)

MLB clubs tend to get what they pay for, with eight of the top 10 teams in terms of payroll currently sitting above .500, Axios' Jeff Tracy writes.

• Yes, but: Every year also features a handful of outliers — teams punching above or below their weight class — and 2021 is no different.

The state of play: The Dodgers' payroll ($267M) is 31% larger than the second-place Yankees' ($203M), per Spotrac, and all six last-place teams fall in the bottom half of that list.

• Among the top 10, only the Angels and Mets are sub-.500, thanks in part to injuries (Jacob deGrom, Mike Trout, Anthony Rendon).

The big picture: The "Moneyball" A's wrote the playbook for maximizing production on a small budget. 20 years later, Oakland is still a poster child for that brand of team building.

• The A's and the Mariners are both in the bottom 10 of payroll, but young talent and team-friendly deals have them in the thick of the AL Wild Card race.
• The Rays and Brewers, meanwhile, are in first place despite payrolls under $100 million. Tampa has been doing this for years, and now Milwaukee has wheeled and dealed its way into contention.

Elsewhere ... The Orioles, near the bottom in payroll, have now lost 19 straight games.

Explore the graphic.

Amid the SEC's growing power, the ACC, Big Ten and Pac-12 announced Tuesday that they have formed an "alliance" to navigate the uncertain future of college athletics.

Details: The three conferences, which include 41 schools across 25 states, agreed to tackle specific topics together — including the future structure of the NCAA and social justice issues — all in the name of unity.

"Hopefully this will bring some much-needed stability in college athletics. It will allow people to understand where everyone else stands because some of the events over the last couple of months have kind of shaken the foundation."

Yes, but: The leagues stopped far short of a formal merger; there's no contract. Even the scheduling component, which could produce more marquee football and basketball matchups, won't begin for years due to contractual obligations and how far in advance games are scheduled.

The backdrop: This pact comes amid a summer of sweeping changes. It began in June with a proposal for a 12-team college football playoff, peaked in July with NIL legislation and then the latest domino: Oklahoma and Texas' pending move from the Big 12 to the SEC.

My take ... Forget the "Alliance." This should be called "Sum 41."

🇺🇸 Herschel for Senate: 1982 Heisman Trophy winner Herschel Walker has launched his Senate campaign in Georgia with former President Trump's support.

⚾️ Stat du jour: Giancarlo Stanton owns the hardest-hit ball in 16 different MLB ballparks. Next-level strength.

🎾 New book: Veteran tennis writer Christopher Clarey is out with a new Roger Federer biography called "The Master." Here's an excerpt from NYT.

⚽️ La Liga NFTs: Dapper Labs, the company behind NBA Top Shot, will create similar NFT collectibles featuring moments from La Liga, Sportico reports (subscription).

🏀 1-2 showdown: The Sun clinched a playoff berth with a 76-62 win over the Aces in a Tuesday showdown between the WNBA's top two teams.

Incredible.

🎥 Watch: Opening Ceremony highlights (NBC Olympics)

The NCAA has ruled 16-year NBA veteran J.R. Smith eligible to play golf at North Carolina A&T, an HBCU in Greensboro.

• Smith was drafted 18th overall in 2004 out of St. Benedict's Prep (Newark, New Jersey), so this is his first college experience. At age 35, he's 14 years older than his next oldest teammate.
• He wakes up for 6am workouts, attends mandatory study hall and is pursuing a degree in liberal studies. Fellow students were shocked when he showed up on Zoom during class.

What they're saying: Golf coach Richard Watkins says Smith's swing tempo reminds him of four-time major champion Ernie Els.

• "He's a sponge right now. He's picking up everything and he's learning," Watkins told WashPost. "I'm pretty sure he's a trash talker, we just haven't heard it, yet."

The NFL season is fast approaching. While we eagerly await its arrival, we're counting down the league's top 20 players.

• Player: Jalen Ramsey, CB (Rams)
• Age: 26
• College: FSU
• Contract: 5 years, $105M (FA in 2026)
• 2020 stats: 15 games; 1 interception, 9 pass deflections
• Week 1: Bears at Rams

The big picture: Ramsey is so dominant that his counting stats look modest. Opposing QBs often prefer to avoid challenging him altogether.

• Last year — Ramsey's first full season in L.A. — the Rams made him the highest paid defensive back in NFL history.
• Wild stat: Stefon Diggs, Terry McLaurin, Allen Robinson, Mike Evans, DK Metcalf and DeAndre Hopkins combined for 584 catches, 7,619 yards and 47 TD last year. In eight games against Ramsey, they totaled just 12 catches, 145 yards and a single TD.

What they're saying: "He senses that fear," said McLaurin. "He's going to try to embarrass that receiver and embarrass that offense and let you know about it."

ICYMI: 20. Dalvin Cook; 19. Trent Williams; 18. Bobby Wagner; 17. Tyreek Hill; 16. Jaire Alexander; 15. Stefon Diggs; 14. Myles Garrett

61 years ago today, the Games of the XVII Olympiad opened in Rome.

Why it matters: These were the first Olympics televised in the U.S., helping turn athletes into superstars like never before.

• Fun fact: Because broadcast satellites didn't exist yet, CBS had to fly its tapes to New York every day to air its coverage.

The big picture: Four athletes stood out above the rest for their performances in Rome and celebrity status once they returned home.

• Cassius Clay: Just 18 years old, and four years from changing his name to Muhammad Ali, "the Greatest" won light heavyweight gold. Two months later, he fought in his first professional match.
• Wilma Rudolph: The 20-year-old sprinter from Tennessee conquered poverty, racism and polio to become the first American woman to win three gold medals in a single Games (100, 200 and 4x100 relay).
• Abebe Bikila: The Ethiopian marathoner was such a late addition to the team that he didn't have suitable shoes for his race. No matter — he ran barefoot and set a new world record as the first of many Olympic gold medalists from sub-Saharan Africa.
• Rafer Johnson: The reigning silver medalist in the decathlon put on an even better show in 1960, going toe-to-toe with Taiwan's C.K. Yang — who happened to be Johnson's roommate at UCLA — to win gold.

🎥 Watch: 1960 Opening Ceremony (YouTube)

Yadier Molina, who will return to the Cardinals for a 19th season in 2022, ranks fourth all-time in games played as a catcher (2,081).

• Question: Who ranks first?
• Hint: Their careers overlapped.

Answer at the bottom.

Dodgers left fielder A.J. Pollock reached out amid a sea of fans and robbed what would have been a two-run HR by Manny Machado.

Full video.