For Doc Rivers, it probably has been the most difficult offseason during his time coaching the Los Angeles Clippers.

The Clips traded away face-of-the-franchise Blake Griffin last season and missed the playoffs for the first time with Rivers in charge, continuing a trend of decreasing win totals in each of his first five years after starting with 57 and a Pacific Division title in 2013-14.

Then in June, his son was traded.

Austin Rivers flourished during his 31⁄2 years in L.A., the first time in NBA history a father was able to coach his son, but was traded to Washington for center Martin Gortat.

When Austin, then 22, arrived in January 2015, following a pair of three-team trades that sent him from New Orleans to the Celtics and out to the Clippers, he was averaging 6.9 points per game in less than 22 minutes a night.

He developed into a full-time starter last season (59 starts in 61 games), and set career-highs in nearly every statistical category, averaging 15.1 points, 4.0 assists and making 37.8 percent from 3-point range.

“He’s grown so much more, just look at his numbers last year. His numbers were off the chart. He came into the league at 20 and he grew,” Rivers said. “That’s what you want your players to do and that’s what he did.”

Getting a chance to see his son develop before his eyes on the game’s biggest stage is something that Rivers will always remember, even though it included seeing him eventually dealt.

“It wasn’t difficult in the fact that I think he is going to a great place,” Rivers said of the move to the Wizards. “It’s just difficult in the fact there’s nothing in a manual that says how to trade your own son. At least I haven’t read that coach’s manual.

“Austin made it so much easier with how he handled it and what he said. He said at the end of the day, we did something that had never been done — a dad got an opportunity to coach his son in the NBA. Who would have dreamt that? I’ve had that opportunity.”

The father and son tandem will be on opposing benches once again on Oct. 28 in Los Angeles, and Nov. 20 in Washington.

Meanwhile, everyone is still trying to catch Golden State after its second title in three years.

“Every conference is only as good as its best team. Golden State is still the best team in the West, so until someone beats them that’s what you’re chasing,” said Rivers, who will participate in the Hoop Dreams fundraiser with Celtics coach Brad Stevens Sept. 4 at TD Garden. “The West is just hard, but I accepted hard long ago. If you want to win the title someday then it should be hard, and the West is hard. That’s just part of it, having LeBron (James with the Lakers) in it makes it that much harder.”

Rivers said that the Celtics are “a favorite for sure” in the Eastern Conference, but stopped short of putting them in the NBA Finals, noting that even though James left the conference, the trade that sent Kawhi Leonard to Toronto meant the conference added “the second- or third-best player” in the league.

Rivers and the Clippers will be in Boston on Feb. 9, while the Celtics visit the Clips on March 11.