The Celtics' pursuit of the 18th NBA title in franchise history has been led by one of the game's sharpest young minds.
Joe Mazzulla is in his second season as an NBA head coach and is largely responsible for Boston posting the best offensive rating in NBA history in 2023-24. Mazzulla's path to becoming an NBA head coach was far from traditional and resulted in him being the NBA's youngest head coach.
In addition to being the youngest head coach in the league, Mazzulla is younger than Celtics veteran center Al Horford, among many other NBA players.
How old is Mazzulla? Here is more perspective on the age of Boston's head coach.
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How old is Joe Mazzulla?
Mazzulla is 35 years old. He was born on June 30, 1988.
A native of Johnston, R.I., Mazzulla graduated from Bishop Hendricken High School in 2006 and pledged to play basketball collegiately at the University of West Virginia.
Mazzulla played five years at West Virginia, leading the Mountaineers to the Final Four in 2010. One of the biggest wins of Mazzulla's college career came against DeMarcus Cousins, John Wall and Kentucky in the 2010 Elite Eight.
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Joe Mazzulla coaching career timeline
After his playing career ended in 2011, Mazzulla began coaching as an assistant at Division II Glenville State in West Virginia.
Mazzulla spent two years as an assistant at Division II power Fairmont State before joining the Celtics organization as an assistant coach for the then-Maine Red Claws, the franchise's NBA G League affiliate.
Mazzulla bounced back to Fairmont State for his first head coaching job, spending two seasons on the sideline before leaping to the NBA as an assistant coach in Boston. He was promoted into the interim head coach position after Ime Udoka was suspended indefinitely and later hired as the franchise's head coach in 2023.
| Team | Role | Years |
| Glenville State | Assistant coach | 2011-13 |
| Fairmont State | Assistant coach | 2013-16 |
| Maine Red Claws | Assistant coach | 2016-17 |
| Fairmont State | Head coach | 2017-19 |
| Boston Celtics | Assistant coach | 2019-2022 |
| Boston Celtics | Interim head coach | 2022-23 |
| Boston Celtics | Head coach | 2023-Present |
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Who is the youngest coach in the NBA?
Mazzulla is the NBA's youngest coach, followed by Utah's Will Hardy. During Boston's run to the 2022 NBA Finals, both Mazzulla and Hardy were members of Ime Udoka's coaching staff.
| Rank | Name | Age | Tenure |
| 1. | Joe Mazzulla, Celtics | 35 | 2022-Present |
| 2. | Will Hardy, Jazz | 36 | 2022-Present |
| 3. | Mark Daigneault, Thunder | 39 | 2020-Present |
| 4. | Charles Lee, Hornets | 39 | 2024-Present |
| 5. | Taylor Jenkins, Grizzlies | 39 | 2019-Present |
There are five NBA coaches under the age of 40. Celtics assistant Charles Lee, who was hired as the Hornets head coach beginning in the 2024-25 season, will turn 40 in November. Grizzlies head coach Taylor Jenkins will turn 40 in September.
How many active NBA players are older than Joe Mazzulla?
18 players older than Mazzulla played at least one game in the 2023-24 NBA season. Among them, eight have played in the 2024 NBA Playoffs.
In addition to coaching Horford, Mazzulla will coach against Indiana's James Johnson, who turned 37 in February.
| Name | Age | Date of birth |
| LeBron James | 39 | Dec. 30, 1984 |
| P.J. Tucker | 39 | May 5, 1985 |
| Chris Paul | 39 | May 6, 1985 |
| Taj Gibson | 38 | June 24, 1985 |
| Kyle Lowry | 38 | March 25, 1986 |
| Garrett Temple | 38 | May 8, 1986 |
| Al Horford | 37 | June 3, 1986 |
| Jeff Green | 37 | Aug. 28, 1986 |
| Wesley Matthews | 37 | Oct. 14, 1986 |
| James Johnson | 37 | Feb. 20, 1987 |
| Danny Green | 36 | June 22, 1987 |
| Joe Ingles | 36 | Oct. 2, 1987 |
| Mike Conley | 36 | Oct. 11, 1987 |
| JaVale McGee | 36 | Jan. 19, 1988 |
| Stephen Curry | 36 | March 14, 1988 |
| Brook Lopez | 36 | April 1, 1988 |
| Robin Lopez | 36 | April 1, 1988 |
| Thaddeus Young | 35 | June 21, 1988 |
| Joe Mazzulla | 35 | June 30, 1988 |