As his shot abandoned him during the opening weeks of his 17th NBA season, Tim Duncan did what he’s done so often before: Put his head down, done the work and trusted the process.

While others typically do shooting work with the help of a coach or teammate, it wasn’t uncommon to see Duncan pull out the large shooting machine — a giant mobile net, with a mechanism to feed the ball back to the shooter — from its dusty corner on the Spurs practice courts to get extra work in.

Ear buds completed the solitary endeavor, brooking no interference as he sought to knock the rust of his 37-year-old limbs.

His efforts appears to have paid off. While so many of his teammates are just trying to get healthy for the stretch run, Duncan is only getting stronger. His vintage performance in Boston on Wednesday, with 23 of his 25 points coming in the second half, continued a string of 19 straight games in double-figures.

Duncan is averaging 17.9 points, 11 rebounds and 2.3 blocks in that span — virtually identical to the numbers he put up last season to earn first-team All-NBA honors, and a massive improvement over a poor start in which he shot 37.5 percent over the first 10 games.

Duncan was a shell of himself at that point. Given his age and mileage, it was fair to wonder if that seemingly bottomless well of excellence had finally fun dry. Turns out he just needed a little time to warm up, kind of like an old but reliable car on a cold morning.