CLEVELAND, Ohio – Dan Gilbert didn't put 20,000 gold T-shirts on the seats at The Q just because.

The Cavaliers and Oklahoma City Thunder didn't land on the slate of ABC's first Sunday games this season for laughs.

Though it took place on Jan. 25, three full weeks before the All-Star Game in a regular season that starts before Halloween and goes past Easter, it truly was a big game.

And for once, the Cavaliers prevailed.

"We've improved, mentally more than anything," LeBron James said Sunday, following Cleveland's 108-98 win over the Thunder.

Remember, James said once this was a "very fragile" team.

"Big game" is a cliché in sports, certainly on most nights when it's applied to describe one contest out of 82 in the NBA. But it's a point worth examining to measure how much James' team has grown over the last several days.

First - and really it's the reason this game was announced for ABC's first Sunday slate back in August - it was a feature of the league's last two Most Valuable Player winners in James and Kevin Durant -- two stars who were picked to lead their teams to, excuse the word, big things this year.

With the Cavs and Thunder playing in opposite conferences, James and Durant only square off twice a year, unless they meet in the Finals as they did in 2012. Basketball fans were robbed of one James-Durant showdown when the Cavs' superstar sat out with a sore knee on Dec. 11.

Next, and schedulers couldn't have known this way back when, but Dion Waiters made his return to The Q after getting traded to Oklahoma City on Jan. 5. It's a side-story, but a juicy one nonetheless.

Third (we're building toward something here), those gold T-shirts draped over each seat at The Q. The idea, of course, is to make the organization and city look (and sound) good on national TV.

Free, gold Cavs T-shirts are reason to scream a little louder, a little more often. Of course, Gilbert picked up the tab.

Add it all together: marquee individual matchup, the whole country watching, intriguing side stories, and nervous energy in the building (more so than on an average night).

The Cavaliers had played in that kind of cauldron of attention exactly twice this season. The first was James' official return to Cleveland on opening night against the Knicks, which James said was "one of the biggest sporting events ever;" and on Christmas Day in his emotional return to Miami.

James and the Cavaliers failed. Twice.

"In those two games we did, yes, obviously, we did," Cleveland coach David Blatt said. "I can't deny that. Hopefully we learned from that."

Though admitting what the entire country saw on those two nights against the Knicks and Heat – that the Cavs played tight and faltered down the stretch – Blatt nevertheless didn't like the comparison.

Before Sunday's game he wondered aloud why a matchup with the Thunder was any different than, say, last Monday's 108-94 win over Central Division-leading Chicago.

Interesting question. The Cavs have beaten the Bulls twice, once following that season-opening dud and last week on the first night at home after a five-game Western trip.

Given that Cleveland still trails Chicago by 3.5 games in the division, each and every game between them is vitally important.

But neither set of circumstances surrounding the Cavs' two wins against the Bulls matched what was going on at The Q Sunday, or on opening night, or in South Beach at Christmas.

In that first game against New York, a nervous James scored 17 points but committed eight turnovers. In his emotional Miami return, James scored 30 points, but there were four turnovers, a really slow opening quarter and some leg issues that briefly knocked him out of the game.

Yesterday, James started 1-of-5 from the field and was called for traveling. But something was different about his early struggles this time, they seemed to come within the flow of the game and because of a bad bounce or two.

When it was all over, James scored 34 points, grabbed seven rebounds, and dished out five assists in 39 minutes. Durant countered with 32 points, six rebounds, and nine assists, but he and his team were defeated by a James explosion to start the fourth quarter.

After Durant shut out James in the third, the Cavaliers' leader returned and scored the game's next eight points. He finished by splashing a 3-pointer on Waiters with 9:43 left, and Cleveland led 91-80. That was about it for the Thunder.

"I wanted to bump it up and be aggressive," James said.

After each of the last six Cleveland games – all wins – players, coaches, general managers and reporters have all talked about the Cavaliers being a changed team.

James looks healthy. Timofey Mozgov, J.R. Smith, and Iman Shumpert add new dimensions. The team defends and believes.

But what transpired Sunday was yet another sign things have evolved in the right direction for James and the Cavs.

They've beaten every team in front of them in the East, and won games over Western teams like Memphis and the Clippers. And yet, Cleveland hadn't won a game like this one all season.

"We're a confident bunch, but for us, we're a humble bunch," James said. "It's one game, against a very experienced team, a very talented team, very good team that's been together for a while and it shows that we can match up with that caliber team."

"I felt the atmosphere was a playoff atmosphere," Blatt added. "I'm glad we responded well to that kind of matchup."