Jarrett Allen has quickly developed a reputation as one of the NBA's most effective shot blockers through just two NBA seasons. During the 2018-19 season, he seized the starting center job in Brooklyn and helped Brooklyn make the postseason for the first time since 2015. Allen averaged 1.5 blocks per game in 2018-19 despite playing just 26 minutes per contest. He began the 2018-19 season with at least one rejection in each of Brooklyn's first seven games. Allen blocked at least three shots on a dozen different occasions, including a season-high six blocks against Cleveland on Feb. 13. The 22nd overall selection in 2017 also set career highs in points (10.9) and rebounds (8.4) per game and doubled his assists to 1.4 per contest. Allen does most of his offensive work around the rim. He finished the season shooting 59 percent from the field, a small improvement over his rookie season. Allen's Nets lost to the Sixers in the first round of the playoffs. Allen started all five playoff games for the Nets, averaging 11.0 points, 6.8 boards and 0.6 blocks per contest.

Allen made his NBA debut in the second game of the season, scoring nine points while shooting 3-for-3 from the field and grabbing two rebounds in a win over Orlando. The 22nd overall pick would appear in 72 games - making 31 starts - and average 8.2 points, 5.4 rebounds, and 1.2 blocks per game. He hit double-digits for the first time when he dropped 12 points along with six rebounds against Atlanta on Dec. 2. Allen would record four double-doubles on the year, the first coming in January when he notched 12 points and 11 rebounds versus Oklahoma City. He'd go on to score 13 points and a season-high 14 rebounds against Detroit on Feb. 7. Allen also dropped a peak of 20 points against the Lakers on Feb. 2. He recorded a season-high seven offensive rebounds during a 15-point, 13-rebound game against Sacramento on Mar. 1. He produced a high of five rejections against Milwaukee on Apr. 5. Allen shot .776 from the line, draining 114 of his 147 attempts. He'd also go on to lead the Nets with 144 offensive rebounds.