Adrian Beltre, who knows something about playing third base, counts himself among Matt Chapman’s growing legion of fans.

Beltre, a four-time All-Star and five-time Gold Glove winner, offered a ringing endorsement of Chapman, the A’s third baseman, before Monday night’s game at the Coliseum.

“What I’ve seen and heard is this guy might be the best third baseman because of how quick he plays the position and how comfortable he feels in the big leagues already,” Beltre said to Texas reporters, expanding on what he told The Chronicle in September.

“For me, over the last 10 years, it would be between (Manny) Machado and (Nolan) Arenado for the best in baseball. I can’t say he’s better than Machado right now, but he does make a case. He’s been playing third base like I haven’t seen in a long time.”

Beltre, 39, acknowledged he doesn’t watch Chapman, 25, play every day. Beltre has been impressed with the variety of plays he has seen Chapman make.

“He makes every play: in, back, diving left, diving right,” Beltre said. “He’s got a really good, strong arm. It seems like he’s really fluid there. … I like the fact he’s good at it but doesn’t act like he’s good at it. I’m a big fan.”

Ticket update: Chris Giles, the team’s chief operating officer, said the A’s have sold more new ticket plans for 2019 in the past 2½ weeks than they did for all of 2018.

“And there are no signs of slowing down,” Giles said.

The A’s also had manager Bob Melvin and pitcher Sean Manaea manning the phones in their offices Monday, in a good-natured twist to the campaign.

“I did make a sale, so I’m expecting a little bit of a commission from that,” Melvin said, smiling.

Now Playing:

The club announced that 2019 A’s Access members are eligible for benefits starting Sept. 1. They will receive 50 percent off concessions, 25 percent off merchandise and $10 prepaid parking during the final month of this regular season.

Busy stretch: Monday night’s game was the fourth in a stretch of 20 games in 20 days for the A’s, through Sept. 5. This influences how Melvin spreads the workload among his relievers.

“You have to take it easy sometimes on the bullpen,” he said. “There will be guys getting some days off, guys who probably need one.”

Chronicle staff writer Susan Slusser contributed to this report.

Ron Kroichick is a San Francisco Chronicle staff writer.