The one-time All-Star point guard, thought to be the face of the franchise four years ago when the team moved to Brooklyn, opted for a buyout of his lucrative contract so he could sign on at a discounted rate with his hometown Dallas Mavericks.
''Things have changed significantly,'' said forward Joe Johnson, who begins his fourth season with the Nets. ''I have to step out of my comfort zone and take it upon myself to be a leader. I have to be more vocal.''
Johnson had his toughest season in more than a decade last season, averaging 14.4 points (his lowest since 2003) and shooting 43.5 percent from the floor and 35.9 percent from 3-point range, both below his career average.
The 6-foot-7 Johnson, who enters his 15th NBA season, spent the offseason wondering whether he would be the next to be sent packing as the Nets tried to rebuild from a failed championship rush.
''We had to shake things up a little,'' he said, adding that he wasn't surprised to hear his name in trade rumors. ''With my contract (an expiring deal for $24.8 million), I kind of expected it, but fortunately, I'm still here.''
Jarrett Jack, a 10-year NBA journeyman, is expected to start at point guard this season in place of Williams. Jack only started 27 games last year (compared with 55 for Williams), but managed to score 12 points and average 4.7 assists (compared with 13 points and 6.6 assists per game for Williams).
Jack said he's not trying to replace Williams, who spent five seasons with the Nets.
''I just have to be myself,'' Jack said. ''Being Jarrett Jack has worked pretty well for me in the past. That's all I want to keep doing. We have some different personnel to work with.''
Jack said that he spoke with Williams on the phone Sunday.
''Sometimes, a change is necessary,'' Jack said. ''He's getting a fresh start, a clean slate. When you leave a place, it's like a breath of fresh air. He's going home. You can't fault anyone for that.''
Jack said that he's ready to be the Nets' starter at point guard.
''It's a role that I've always tried to be in,'' he said.
Center Brook Lopez, who opted out of his final year of his contract then signed a three-year, $64 million deal in the offseason, enters camp as the main man in the middle.
''I'm ready for the opportunity,'' said Lopez, who averaged 17.2 points and 7.4 rebounds per game last year in a breakthrough campaign. ''I want to be the guy to lead this team on and off the court. I know they can count on me as being the go-to guy. It's weird that I'm only 27, but I'm already one of the veterans on the team. ''
Lopez says he's healthy this season. He played in only five games in 2011-12 and then 17 in 2013-14.
''It was great that instead of rehabbing, I was actually out on the floor this summer,'' Lopez said. ''We do have a lot of new faces this year, so it's an opportunity for me to surprise some people and prove that I'm more of a complete player.''
The Nets also re-signed Thaddeus Young to a four-year, $54 million deal after Young came to the Nets in a trade for Garnett last February. Young averaged 13.4 points and 5.7 rebounds per game for the Nets after the trade.
''I think we're going to be able to compete and play well,'' Young said.
The Nets finished 38-44 last year, but lost to regular season Eastern Conference champs Atlanta in the playoffs.
''I have a vision about this team,'' coach Lionel Hollins said. ''The question is, can we do it? I think we've added depth, some players who have played in the NBA. Last year, we had a bench to start the year who didn't play at all.''
Some of the newcomers include former No. 1 overall pick Andrea Bargnani, journeyman swingman Dahntay Jones, former No. 1 pick Thomas Robinson and highly touted top pick Rondae Hollis-Jefferson of Arizona.
The Nets open the 2015-16 season with a game against the Chicago Bulls at home on Oct. 28.