ORLANDO, Fla. -- When the Boston Celtics signed Al Horford to the largest free-agent contract in franchise history this summer, they knew they were getting a player who could quarterback their defense. What they maybe didn't expect was getting a player who was capable of quarterbacking their offense, regardless of whether Boston's All-Star point guard was on the floor with him or not.

Coming into the 2016-17 campaign, Horford’s 10th NBA season, the 6-foot-10 big man had registered eight or more assists just seven times in his career. He has done it three times in 12 games with Boston, including in both of Boston's games this week.

What's more, the 30-year-old Horford was Boston's outright assist leader in each of those games, totaling nine assists in Monday's loss in Houston and eight in Wednesday's win in Orlando. Before this week, Horford had been the outright assist leader for the Hawks just five times in 578 regular-season games.

Al Horford has shown he is capable of running the Celtics' offense and is averaging 5.3 assists per game so far this season. Eric Hartline/USA TODAY Sports

Horford has always been an extremely unselfish big man capable of creating opportunities for his teammates. But Boston's offense has routinely kicked into overdrive with him on the floor, in large part because he has embraced a facilitator role as Boston tries to work the ball through him in the post.

According to the NBA’s player tracking data, Horford is averaging 50.8 passes per game this season. For means of comparison, that’s just two passes less per game than Steph Curry averages in Golden State’s pass-happy offense. The NBA has a metric called assist points created that tracks the total number of points generated by a player’s assists. Horford is averaging 12.3 assist points created per game this season. That’s the 24th highest total in the NBA among players with at least 10 games played. Horford is creating more points than many of the primary ball handlers on opposing teams (Curry's 13.8 assists points created is only five spots higher than Horford).

Horford’s assist percentage stands at a career-best 23.8 percent this season. According to Basketball Reference, only 18 players that were 6-foot-10 or taller have ever averaged an assist percentage higher than 23 percent while playing at least 1,500 minutes in a season. Among players that size, Horford is fourth in the NBA this season behind only Blake Griffin, Giannis Antetokounmpo and Marc Gasol, but only Antetokounmpo averages more assists per game.

Horford, who has averaged 2.8 assists per game over the course of his career, is handing out a career-best 5.3 assists per game for Boston this season. Like any good distributor, Horford is quick to shovel all the praise on his teammates for the uptick.

"Coach is calling my number to make plays, and honestly, the guys are just cutting great to the basket, and I’m finding them," Horford said. “It’s a lot of easy looks. So it’s really their [off-the]-ball movement. I’ve been really impressed with Avery [Bradley], with Jae [Crowder], with their ability to read the defense and get those open looks.”

Bradley (19 assisted baskets by Horford) and Crowder (12) have been the largest beneficiaries of Horford’s distribution, but Horford does not play favorites. He has assisted 11 different teammates through 12 games. And consider this: Bradley has more makes off Horford assists this year than from his starting backcourt partner Isaiah Thomas (17), despite playing in nine more games with Thomas (Horford/Bradley have 327 minutes of floor time together compared to 555 minutes for Thomas and Bradley).

With Thomas sidelined by a groin strain on Wednesday, Horford's increase in distribution could be expected. But his numbers were already climbing when Thomas was on the court on Monday in Houston. Stevens admitted that Boston's offense has often looked its best when Horford shows off his passing abilities.

“We’re always trying to attack the paint first," Stevens said. "One of the things that we want to do, especially in Isaiah’s absence, was play through our bigs and through the post. [Wednesday’s] game started really going our way when we did that and passed out of the post, had a bunch of cuts off of it, guys were active, and Al’s such a good passer down there that it’s a good action for our team."

The Celtics had 22 post touches during Wednesday’s win, which is 6.3 more touches than their season average, according to the league's tracking data. Boston has clearly identified that good things happen when either guards penetrate into the paint or Boston gets the ball to Horford with an ability to distribute to cutters.

Even beyond his passing skills, Horford has been nothing short of spectacular for Boston. The Celtics own a team-best net rating of plus-11.1 with Horford on the court, and they are minus-1.7 when he goes to the bench. Maybe hammering home his impact on Boston's offense, the Celtics' offensive rating dips 10.7 points when Horford is off the floor.

For the season, Horford is also averaging 15 points, 6.4 rebounds and 2.6 blocks per game. The Celtics are a team-best plus-83 in his 389 minutes of floor time and a team-worst minus-39 in the 667 minutes he has been off the court.

Horford admits he's still figuring out the best ways for him to impact the team when he's on the court, even as Boston's numbers have sparkled with him on the floor.

"I’ll continue to take what the defense gives me. That’s the way that I’ve always played," Horford said. "One of the things is for me to get comfortable with the offense -- what we’re trying to do -- and knowing when to pass the ball and when to shoot it."