Al Horford will bring consistency and defense to Boston Celtics

Al Horford should be a major presence in the post for the Celtics. Dale Zanine/USA TODAY Sports

The Boston Celtics took a big step forward with the reported agreement with free agent Al Horford on a four-year contract.

Horford became the latest beneficiary of the NBA’s salary-cap increase from $70 million to $94 million. His reported $113 million deal is the first nine-figure contract in Celtics history. Horford's first-year salary represents 28 percent of this season's salary cap. It would have represented 38 percent of last season's cap.

With Horford, you know what you’re getting. He averaged 15.2 points, 7.2 rebounds and 3.2 assists in 2014-15, and then 15.2 points, 7.3 rebounds and 3.2 assists in 2015-16. He’s a four-time All-Star who made the Eastern Conference team in each of the past two seasons.

The area in which Horford’s game has changed the most is his outside shooting. He made 21 3-pointers in his first eight seasons. He made 88 of them last season.

Horford ranks as one of the league’s best post defenders, as shown through video review. Horford defended 262 direct posts in the 2015-16 regular season (that's a post-up attempt in which a player shoots, is fouled, turns the ball over or passes to a shooter), more than any other player in the NBA.

He allowed players to score 0.84 points per direct post. Among the top 12 players with the most direct posts defended, only defensive player of the year runner-up Draymond Green allowed fewer points per direct post (0.72).

Horford had a career-high 121 blocked shots in 2015-16 and will fill a need there; the Celtics ranked 22nd in the NBA in blocked shots. Last season was the first in which he played all 82 games.

As to how this impacts the potential acquisition of Kevin Durant, consider this:

The Celtics will have enough cap space to offer Durant a maximum contract if they waive both Amir Johnson ($12 million) and Jonas Jerebko ($5 million); they have until July 7 to do so, otherwise the deals become fully guaranteed. Restricted free agents Jared Sullinger ($5.7million cap hold) and Tyler Zeller ($6.5 million cap hold) would need to be renounced as well in that scenario.