Bill Belichick has been doing it a long time, approaching the midway point of his 24th season as Patriots coach. The all-timer has predictably spawned a big coaching tree along the way, with 10 former assistants going on to become NFL head coaches. But with the Raiders' abrupt dismissal of Josh McDaniels halfway through the 2023 campaign, only a single Belichick disciple currently holds a top job. Which ones have panned out? And which ones may have been better served staying under his wing?
Here's how we'd rank each of the 10 NFL head coaches to emerge from under the Patriots great:
10. Joe Judge
NFL head coaching jobs: Giants (2020-2021)
Career record: 10-23
A longtime special teams coordinator under Belichick in New England, Judge brought bravado to his press conferences, but it didn't translate. The bar was set low after dismal two-year stints with Ben McAdoo and Pat Shurmur, but his teams -- despite occasionally feisty defenses -- never materialized on offense and threw in the towel late.
9. Matt Patricia
NFL head coaching jobs: Lions (2018-2020)
Career record: 13-29-1
The bearded wonder helped Bill win three Super Bowls as the Patriots' defensive coordinator, but he was largely disagreeable in Detroit, guiding some scrappy upsets -- including over Belichick's Pats in 2018 -- but ultimately expediting the future relocation of big names like Matthew Stafford and Darius Slay while failing to sniff the playoffs.
8. Josh McDaniels
NFL head coaching jobs: Broncos (2009-2010), Raiders (2022-2023)
Career record: 20-33
The longtime offensive coordinator was ousted quickly by two different franchises. Controversy followed him, from a reported dispute with ex-Broncos QB Jay Cutler, who left Denver before McDaniels coached a game; to a videotaping scandal that prompted NFL fines. He's proven capable of designing an offense while in New England, but his redemption tour with the Raiders was quickly undone by an overreliance on aging, battered friends from his Patriots days.
7. Romeo Crennel
NFL head coaching jobs: Browns (2005-2008), Chiefs (2011-2012)*, Texans (2020)*
Career record: 32-63
The longtime defensive coordinator is respected and well-liked, hence his repeat role as an interim for failed regimes. But in roughly six seasons of combined experience running the ship, he managed just one winning season and zero playoff bids.
Note: * = Crennel was an interim coach for 15 of his 32 games with the Chiefs and Texans.
6. Eric Mangini
NFL head coaching jobs: Jets (2006-2008), Browns (2009-2010)
Career record: 33-47 (0-1 playoffs)
A defensive assistant under Belichick with both the Jets and Patriots, Mangini started hot, finishing 10-6 and guiding Chad Pennington to Comeback Player of the Year honors in his debut, only to fall to Belichick's Pats in the first round of the playoffs. He never recovered, going 19-29 for the remainder of his career, which included a reportedly alienated locker room in Cleveland.
5. Brian Daboll
NFL head coaching jobs: Giants (2022-present)
Career record: 11-13-1 (1-1 playoffs)
Daboll held three different positions in two different stints under Belichick before taking off at Alabama and as the Bills' OC, then rejuvenating the careers of Daniel Jones and Saquon Barkley to guide a scrappy Giants team to a road playoff win in his HC debut. He quickly fell back to Earth in Year 2, however, as he's failed to overcome a shoddy O-line with curious situational decision-making.
4. Al Groh
NFL head coaching jobs: Jets (2000)
Career record: 9-7
You can't tarnish a legacy that barely exists! Groh, of course, is best known for his long run as Virginia's coach, and a champion Giants assistant, but he spent just one year on the sidelines in New York before resigning to return to college. He at least paved the way for Herm Edwards' tenure -- a five-year run that included three playoff berths and two postseason wins.
3. Nick Saban
NFL head coaching jobs: Dolphins (2005-2006)
Career record: 15-17
A defensive coordinator under Belichick with the Browns, Saban would obviously rank No. 1 if we were including college achievements; he's the NCAA Belichick running the powerhouse that is Alabama. In Miami, he was just mediocre, which is more than most of these guys can say. His broken promise to stick with the Dolphins rather than bolt for the Crimson Tide will always be part of his NFL "legacy," however.
2. Brian Flores
NFL head coaching jobs: Dolphins (2019-2021)
Career record: 24-25
Miscommunication seems to be the chief reason for his departure, with reported disagreements over key spots like QB -- where he tried but failed to acquire Deshaun Watson and/or ride a combo of Tua Tagovailoa and Ryan Fitzpatrick to the playoffs. His teams were also very streaky. Still, considering the barren rebuild he inherited, he always kept Miami in contention with a stout "D." And he might be on his way to another top job after bringing physicality to a makeshift Vikings defense.
1. Bill O'Brien
NFL head coaching jobs: Texans (2014-2020)
Career record: 52-48 (2-4 playoffs)
O'Brien helped leave the Texans in their recent state of ruin, seizing personnel power and even an official general manager title while shipping Pro Bowl stars like DeAndre Hopkins and Laremy Tunsil out of town. But he at least brought toughness and respect to an organization long mired in mediocrity, guiding four playoff runs and two 10-win finishes in just over six seasons.
***
Note: Longtime defensive coordinator Jim Schwartz, who served as Lions head coach from 2009-2013, also worked under Bill Belichick, but as a personnel scout. His biggest achievement was leading the Eagles' defense during their 2017 Super Bowl run.