Taylor Twellman has long been known for high-level commentary on ESPN's soccer broadcasts. His most famous analysis, though, was a raw cry from the heart.

On the night when the U.S. men's national team failed to qualify for the World Cup — almost a year ago now, by the way — Twellman's "What are we doing?!" lament on live TV touched the deepest of nerves.

An answer has come from, of all places, the Union. Their vocal commitment to developing American players was once seen as hype, but has lately been proven substantial.

Twellman will see the Union's progress in person twice in the next few days. He'll call Sunday's game against West-leading Kansas City (1 p.m., ESPN) and the U.S. Open Cup final at Houston on Wednesday (8 p.m., ESPN2). He likes what he has seen from afar.

"If anyone's not paying attention to the Philadelphia Union now, they're out of their mind," Twellman said.

The Union's focus on development intrigues him. It's a rare thing in MLS.

"I think you'd have a tough time finding five teams that do that," he said. "I find it interesting. There's an identity. There's a game plan. There's 'This is who we are.' "

Part of that identity, Union brass have said, is a willingness to sell players abroad when fair offers come in. Twellman is encouraged, but still a bit skeptical.

"I'll believe it when I see it," he said. And he doesn't count flashy deals such as Vancouver Whitecaps phenom Alphonso Davies' $13.5 million move to Bayern Munich, which he dismissed as a "one-off."

He wants "what the rest of the world is doing": a greater quantity of sales for lesser sums.

Two Union players who've attracted foreign interest, Auston Trusty and Derrick Jones, had huge games in the Union's recent upset of the Sounders in Seattle.

"To get that result with the schedule you have coming up, it just tells you the kind of job Jim Curtin and that staff have done," Twellman said. "That is a result that more often than not, it propels you to an Open Cup championship; it propels you to making the playoffs."

It also put fourth place back within reach. The gap between the Union and Crew is again down to one point, and the teams will meet in Columbus on Sept. 29. Columbus has an easier remaining schedule than the Union, but the Union's win in Seattle convinced Twellman that the Crew can be caught.

"I think Columbus is under-performing, and I think that game at the end of September could prove the difference," he said. "That result at Seattle has convinced me that anything is possible right now."

Union vs. Sporting Kansas City

Sunday, 1 p.m. at Talen Energy Stadium

TV/online streaming: ESPN, ESPN Deportes, ESPN.com/Watch

Union's record: 13-12-4, 43 points (5th in the East); 7-5-2 at home
Kansas City's record: 15-7-6, 51 points (1st in the West); 6-5-3 on the road

Series history: Union 5 wins, Kansas City 7 wins, 5 ties
At Talen Energy Stadium: 3 wins, 3 losses, 2 ties

Kansas City players to watch

M Felipe Gutiérrez: Even many close watchers of MLS don't know much about Sporting's best players. Manager Peter Vermes, a Delran native, has a superb track record of turning under-the-radar names into key contributors. Gutiérrez, a Chilean with a huge engine, is a great example.

D Ike Opara: A smart, skilled centerback who's now in his sixth year as a Sporting stalwart. He was MLS' defender of the year last season, but arguably still doesn't get the respect he deserves.

M Johnny Russell: The Scotland native was found at English second-tier club Derby County, and now leads Sporting in goals and assists (8 of each). He's done so well that in May, the Scottish national team brought him back to the squad for the first time in two years.