When Mo Williams arrived in Cleveland ahead of the Cavs training camp in September, he had a meeting with several members of the coaching staff to outline some of the plans they had in store for him with his new teammates.

The coaches had a lot of things to say; Williams only had one: "Whatever you need me to do, on the ball, off the ball, I'm cool with it all."

The early success the Cavs have enjoyed this season -- a 19-3 start and a 10-game winning streak after their 101-93 road victory over the 76ers on Wednesday -- began last spring when the restructured team began to gel in the playoffs. It continued over the summer as LeBron James gained extreme confidence as one of the leaders of Team USA.

And when Williams came aboard, bringing both the talent the Cavs were sorely lacking -- a high-level offensive point guard -- and a team-first attitude from his first day on the job, many of the Cavs' well-chronicled deficiencies started melting away.

Williams and James are now running the show of what so far has been the best offense in the NBA. That's a fairly shocking statement considering the way the team had performed in the James era.

Averaging 104 points and just 13 turnovers per game and shooting 48 percent, the Cavs thus far have the most efficient offense in the league. Seven players average seven points or more, and nine players are shooting 46 percent or better. Until Wednesday, each of the Cavs' past 12 wins had been by at least 11 points.

"When you look at the depth we have, we know we can score with anyone in the league," James said. "It doesn't just have to be me."

Could one player, Williams, have made that much of a difference? Well, yes and no.

For much of last season the Cavs had the lowest-scoring starting backcourt in the NBA. Larry Hughes started most of the games at point guard, but he was playing out of position. Several different players started at shooting guard, including Daniel Gibson, Devin Brown, Shannon Brown and Wally Szczerbiak, and none seemed to perfectly fit.

Things improved slightly when Delonte West was brought aboard, because it meant that Gibson could go back to the bench, the role in which he has performed best during his career.

Last year the Cavs were actually outscored by their opponents, and things improved only slightly in the postseason, when Cleveland still averaged less than 90 points and shot 42 percent. When the Cavs did win, most of the time it was because James -- who without a doubt had his best season as a pro in winning the scoring title and leading the league in fourth-quarter scoring -- carried them home.

Bringing in Williams, though, changed more than just one position. Knowing they had a lead guard who could run the offense on his own, the Cavs were able to move West over to shooting guard. That is his best position, in which he excelled in college at St. Joseph's next to Jameer Nelson.

That move not only allowed Gibson to come off the bench, but also Szczerbiak, who played well for the Sonics as a reserve last season before going stone-cold as a starter with the Cavs. So by adding Williams to the mix, the Cavs were able to position their top four guards to be successful, and successful they have been.

West's shooting has been strong, and he's averaging just under 10 points, with a 3-to-1 assist-to-turnover ratio. Because he is also the Cavs' best on-ball perimeter defender, he's been able to match up with tougher point guards on defense without having to handle too much on offense.

Because James doesn't have to handle the ball as much either, the Cavs have been able to play smaller and allow him to play some at power forward. Szczerbiak also gets chances there; his lack of quickness doesn't show up as much when he plays inside. But with Williams and James on the floor creating, Szczerbiak still gets open looks on the outside. And the benefit is clear: After shooting 36 percent with the Cavs last season, Szczerbiak is now at 48 percent.

Williams' scoring and assist numbers down slightly from last season. He's at a bit less than 16 points and five assists per game, but he's just as involved. Coach Mike Brown has set up the rotation to always allow Williams to be on the court when James is resting, so Williams gets to share time as the main offensive option with Zydrunas Ilgauskas.

Williams can take over when he needs to, such as when he scored six points in the last three minutes to clinch the win against the 76ers.

Williams has been so effective that James is playing the fewest minutes of his career. Only twice thus far has James played 40 minutes, which was his average last season.

To take advantage of Williams' talents, the Cavs also installed some new facets of their "early offense" so they could be more effective in transition. It was easier to do, considering James didn't have to lead every fast break.

Because Brown trusts Williams to run the offense, he allows Williams to handle much of the play calling. This is a switch from past seasons, and it enables the Cavs to be more fluid because they don't have to wait for a signal from the bench.

"Mo has been off the charts for us," Brown said. "With Mo calling the game it makes us harder to defend, and he's been doing a great job of getting everyone into a rhythm."

Factor in their always strong defense, which ranks first in the league in points allowed and second in field goal percentage allowed, and the Cavs suddenly have the look of a serious championship contender.

"Am I surprised we're 19-3? No, because I believed in this team when I got here," Williams said. "We have a long way to go, but we are focusing on the right things."

ESPN.com contributor Brian Windhorst covers the Cavaliers for the Cleveland Plain Dealer.

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