In the opening seconds of Stephen Curry’s NBA career he got an assist on the first possession, a steal on the second and then tried a 3-pointer for the first time at the professional level.

It missed.

In that moment, there probably were not very many people expecting he would become the most prolific 3-point shooter in NBA history. Yet as the new NBA season starts Tuesday night, so does the countdown toward Curry surpassing Ray Allen’s mark for 3’s made in a career.

Allen retired with 2,973 3-pointers in regular-season games. Curry is 141 behind, with 2,832 in his career. At his typical rate of 3’s made in recent years — about five per game — the Golden State sharpshooter could have the record by mid-December.

Curry is the only player in NBA history to average at least five made 3’s per game over a full season. He’s done it three times. Curry also has four of the five seasons of at least 300 made 3’s, including a record 402 in 2015-16; James Harden had the other 300-plus season on that list.

Allen never made more than 269 3’s in a season. Curry has topped that on six different occasions.

Some other storylines and milestones to watch this season:

CHASING KAREEM: LeBron James could become the NBA’s all-time scoring leader next season.

He enters the season No. 3 on the scoring list, 1,561 points away from No. 2 Karl Malone’s 36,928 points. Kareem Abdul-Jabbar tops the list with 38,387 points — currently 3,020 ahead of James.

POP’S TIME: San Antonio’s Gregg Popovich has 1,310 career regular-season wins, putting him 26 away from outright possession of the NBA record. He’s currently third on the list, behind only No. 2 Lenny Wilkens (1,332) and No. 1 Don Nelson (1,335).

Popovich is entering his 26th season as coach of the Spurs, extending his NBA record for longevity with one franchise.

CELEBRATING 75: The NBA is celebrating its 75th anniversary this season. The league’s first game was Nov. 1, 1946, when the New York Knicks visited the Toronto Huskies, back in what was then called the Basketball Association of America.

Toronto and New York play on Nov. 1 this season, too: The Raptors visit the Knicks that night.

REMEMBERING WILT: The 60th anniversary of Wilt Chamberlain’s 100-point game is March 2; he had that night in Hershey, Pennsylvania, for the Philadelphia Warriors against the New York Knicks.

Philadelphia (the 76ers) will play the Knicks on March 2 this season as well, in Philadelphia, not Hershey.

GOLD RUSH: There are 29 players in the NBA this season with at least one Olympic gold medal, on 15 different teams.

The Lakers lead the way with six players who have Olympic gold — LeBron James, Dwight Howard, Carmelo Anthony, Russell Westbrook, Anthony Davis and DeAndre Jordan.

Golden State (Andre Iguodala, Draymond Green, Klay Thompson) has three Olympic gold medalists, as does Miami (Bam Adebayo, Kyle Lowry, Jimmy Butler) and Brooklyn (Kevin Durant, James Harden, Kyrie Irving).

The teams with two gold medalists are Milwaukee (Jrue Holiday, Khris Middleton), Phoenix (Devin Booker, Chris Paul) and Chicago (DeMar DeRozan, Zach LaVine).

And the other eight clubs all have one: San Antonio (Keldon Johnson), the Los Angeles Clippers (Paul George), Cleveland (Kevin Love), Detroit (Jerami Grant), Sacramento (Harrison Barnes), Portland (Damian Lillard), Denver (JaVale McGee) and Boston (Jayson Tatum).

TEAM MILESTONES: There are some reachable team won-lost marks to watch.

On the good side: Philadelphia is 51 wins away from 3,000 as a franchise, a milestone that only the Boston Celtics and Los Angeles Lakers have reached. And Toronto needs 18 victories to reach the 1,000-win mark.

On the not-so-good side: Detroit is 21 losses away from 3,000, which will have them joining Sacramento, Golden State and New York in that club.

GIANNIS WATCH: It’s only a matter of time before reigning NBA Finals MVP Giannis Antetokounmpo becomes Milwaukee’s all-time leader in most major statistical categories.

He enters this season 1,892 points behind Kareem Abdul-Jabbar (14,211) for the Bucks’ franchise record there. He’s also 1,790 rebounds behind Abdul-Jabbar (7,161) and a mere 39 blocked shots from matching Alton Lister (804) for the Bucks’ career record.

PRESEASON REDUX: It may be time to eliminate Golden State, Chicago, Dallas, New York and Sacramento from NBA title contention.

They went undefeated in the exhibitions.

If any of those teams go on to win the 2022 NBA championship, it would mark the first time that a team went unbeaten in the preseason and won the title since the Chicago Bulls in 1992-93.

MOVING UP: Some other individual milestones to watch:

— Chris Paul is 59 assists away from matching Mark Jackson for No. 4 on the all-time list, and 60 assists away from matching Steve Nash for No. 3.

— Jerry West has the fourth-highest career scoring average (27.030 per game), just ahead of No. 5 Kevin Durant (27.017) and No. 6 LeBron James (26.998).

— Golden State’s Andre Iguodala is eight games shy of 1,200 for his career. The Lakers’ Carmelo Anthony is nine away from that milestone, and 200 field goals away from 10,000.