I cheered wildly when the Seattle Sounders defeated the Philadelphia Union 2-0 in the opening match of the Major League Soccer season.

But when I tried to text a friend, call my wife and check the latest scores in the NCAA men's basketball tournament on my iPhone at last week's match at Qwest Field I was the one who was feeling shut out. And it appears I am not the only iPhone user fed up with poor coverage.

Fans who attend Sounders and Seahawks games at Qwest Field routinely complain of poor cellular coverage at the city's largest sports stadium, pointing fingers at the much maligned AT&T network.

AT&T recognizes the problem and says they're working on ways to offer better service when large crowds gather. Nonetheless, it can get a little ugly when a beer-fueled, iPhone-wielding Sounders fan can't text, talk or Tweet.

Adding to the frustration are the constant marketing messages from AT&T at Qwest Field, which advertises on the field-level billboards that surround the pitch. (Is that good marketing? Advertising a mobile product that fans can't use while at the game?) Even worse, during a half time bathroom break, I heard an ad on the radio broadcast which said: "Keeping up with 3G speed -- a game changer."

Really? Back at the seats, I couldn't even get a signal.

If AT&T were a player, they'd have been issued a red card by now. And, like I said, I am not the only one experiencing these issues.

Sounders season ticket holder Bill Johnson, who sits in section 134, said he loses service on his iPhone 3GS right before kick off, and the problems continue after the game.

"During play, I am not able to send or receive any texts, calls, or data even though I have full coverage," said Johnson. The same goes for John Lusk, also a season ticket holder in section 134. He loses coverage inside Qwest Field, only collecting voice mails, texts and email on his iPhone after leaving the stadium. "It sucks," he says.

So, what's actually going on with the poor coverage?

A spokeswoman for AT&T said that the company's network technicians performed tests during the Sounders' game last week and found "minimal issues that would have affected coverage."

"Our goal is to give our customers the best possible experience on their AT&T devices, so we’re continuously working to optimize coverage, especially to handle larger crowds," said Colleen Smith. Asked in a follow-up email for additional details, Smith suggested that the problem is directly tied to the number of people accessing the network in a concentrated area.

"Fans are now texting, tweeting, surfing, e-mailing and accessing applications throughout the game," said Smith. "To meet the growing demand, we have increased network capacity and speed at Qwest Field, and we plan further network enhancements later this year."

In fact, Bellevue-based Root Wireless -- which independently measures and tracks network performance for the four major carriers -- pinpoints a weak coverage spot in AT&T's coverage on the west side of Qwest Field. That part of the stadium provides average download speeds of just 19 Kbps. Strangely, the weak spot sits next to other areas in the stadium where coverage speeds average 341 Kbps.

Root Wireless' network map shows a weak spot on the west side of Qwest Field.

Some fans have just given up, and there's a fair criticism that real sports fanatics should be paying attention to the game rather than sending a text or Tweet. But behaviors are changing, and some fans like Chris Calabro who Tweets @sportsguyNW like to share their insights about a game in real time.

"I was chagrined when I couldn't even refresh my Twitter page while in the stadium," said Calabro, who wanted to send a Tweet during the final game of the Seahawks' season. "Plenty of signal, just no room at the inn. I wasn't about to spend the whole game wrestling with my phone, so I just let it go."

It may be a minor issue. But for teams partially owned by people who made money in high-tech (Paul Allen for the Seahawks and Adrian Hanauer for the Sounders) the lack of true mobile coverage in a high-tech city like Seattle is an embarrassment. (The Sounders -- sponsored by Xbox Live -- even tout a live Twitter feed on their Web site for fans to post and read messages during the game).

Suzanne Lavender, director of communications at Qwest Field, said fans have complained about the coverage during Sounders and Seahawks games. But there's not much they can do about it. "Unfortunately, with a large concentration of people using cell phones, all of the providers can't keep up," she said.

Last year, Lavender said AT&T tried rolling in a portable cell site during a Seahawks game. But even that didn't resolve the issue.

Some fans are just giving up on AT&T.

Josh Maher, a Sounders season ticket holder, said he always had "horrid" service on his iPhone at Qwest Field. And, partly because of that, as well as other ongoing network issues, Maher recently purchased a Droid phone.

"As a dedicated SoundersFC fan, I am glad I moved to Verizon this season," he said. "Using a Verizon Droid at Qwest Field in comparison to using an AT&T iPhone is like day and night in terms of access to the network and service reliability."

Meanwhile, Johnson has noticed another negative consequence of the poor cellular signal.

"The inability to connect severely limits the effectiveness of my trash talking," he said.

The Sounders take on the New York Red Bulls on Saturday night. I'd ask you to text or send a Tweet to me at the game to connect, but I don't think I'll get it.

[Flickr photos via Kurt Schlosser]