Avery Bradley explains why he feels Jimmy Butler should respect him more and that he has won two battles in a row against him. (1:07)

One year after ascending to the NBA's All-Defensive first team, Boston Celtics guard Avery Bradley was a notable omission when the 2016-17 teams were announced on Monday.

Remarkably, Bradley finished as the top vote-getter in the entire Eastern Conference but did not earn one of the 10 available spots on the league's two five-man teams. Bradley was the 10th-highest vote-getter overall but did not accrue enough points for one of the four guard slots.

In a vote of 100 sportswriters and broadcasters, Bradley finished with 46 total points, including 12 first-team votes. That lagged behind the guard quartet of the LA Clippers' Chris Paul (140 points), Houston's Patrick Beverley (110), Memphis' Tony Allen (80) and San Antonio's Danny Green (68).

Bradley's omission raised eyebrows across the league. Phoenix guard Devin Booker, who scored 70 points against Boston on a night the Celtics were without Bradley, suggested Bradley deserved a spot, while teammate Isaiah Thomas wondered out loud how Bradley didn't land on the list again.

How the hell is Avery Bradley not on the all defensive team?? That's crazy!! — Isaiah Thomas (@Isaiah_Thomas) June 26, 2017

As the trend toward position-less basketball grows, you can make the case that the NBA ought to migrate away from postseason awards in which spots are determined by position. If the seven best defenders in the NBA are guards, shouldn't those seven players be rewarded?

Bradley missed 27 games this season, which undoubtedly contributed to his lack of total votes. Did his numbers in 55 games this past season justify a spot?

Judging a player's defensive contributions is tricky with a lack of trustworthy defensive data. We're left searching for clues. Often players are lauded when a team's defense performs better when they are on the court than when they are off. A look at Boston's defensive ratings with and without Bradley, as compared to the four All-Defense guards:

Def. Rating, On/Off Differential, 2016-2017 DefRtg On DefRtg Off Net Avery Bradley 107.5 103.8 -3.7 Chris Paul 101.3 110.1 +8.8 Patrick Beverly 106.0 106.8 +0.8 Tony Allen 104.4 104.7 +0.3 Danny Green 101.1 100.8 -0.3

While Boston has some highly regarded defenders on its roster -- Jae Crowder, Marcus Smart, and Al Horford chief among them -- the team's numbers were surprisingly underwhelming this season, at least for a team projected to be among the league's best defenses. Boston ranked 12th overall in defensive rating (105.5) in 2016-2017, a drop from being tied for fourth in 2015-2016 (100.9 defensive rating). A case could be made, though, that the team's offense performed at such a high level that it might have contributed to some slippage on the defensive end.

We can get a sense of individual performance via Synergy Sports data. While Synergy's numbers are imperfect, it might be the best available option to gauge guard play. Here's how the five guards performed in points allowed per possession defended and where they ranked among all possible guards with at least 500 total plays defended this season:

Points allowed per possession defended DefPPP Rank* Avery Bradley 0.922 50th Chris Paul 0.907 36th Patrick Beverly 0.886 23rd Tony Allen 0.879 19th Danny Green 0.848 9th *At least 500 total plays defended, 2016-2017 season

Last season, while earning All-Defensive first-team honors, Bradley allowed 0.879 points per play, so his defensive performance slipped a bit this season based on Synergy analysis. Plenty of other metrics suggested Bradley wasn't quite on the All-Defense level this season, at least based on team performance with him on the court. ESPN's defensive real plus/minus finds Bradley lagging behind the pack of All-Defensive guards as well:

2016-2017 Defensive Real +/- Defensive Real +/- Chris Paul 2.76 Tony Allen 2.15 Danny Green 1.71 Patrick Beverley 1.37 Avery Bradley -1.72

Missing 27 games likely left some voters reluctant to vote for Bradley. This isn't without precedence. Rudy Gobert was limited to 61 games during the 2015-16 season and landed in an almost identical situation to Bradley. Gobert's 64 points that season were the ninth-highest total in the league, but he didn't earn a spot on the two teams and finished with the highest total among honorable mentions.

But Bradley was the last player to make an All-Defense team when playing in no more than 55 games; he made the second team in 2012-2013 despite only 50 games played.

While Bradley's 2016-17 numbers weren't seemingly as glitzy as recent seasons, the eye test suggested there was less slippage. Yes, it's a regular-season award, but Celtics fans will point to how Bradley's defense against Jimmy Butler helped Boston rally from a 2-0 deficit in the first round of the Eastern Conference playoffs. Bradley provided one of the signature moments of the regular season when his spellbinding late-game defense on Kyrie Irving helped Boston emerge with an early March victory over the Cavaliers. Heck, there's a seven-minute video of Bradley's best defense this season on YouTube.

At least one NBA player even made a reference to Bradley's defensive impact on the Celtics when he didn't play -- Phoenix Suns guard Devin Booker's 70-point performance in Boston came in a March contest when Bradley was inactive:

No Avery Bradley all-defense?! On the behalf of the players... he deserves it! — Devin Booker (@DevinBook) June 26, 2017

Of course, Bradley being overlooked isn't the worst thing for the Celtics. Boston's players tend to thrive off disrespect. Celtics coach Brad Stevens has repeatedly noted how Boston has constructed a roster brimming with players featuring chips on their shoulders.

Bradley will be highly motivated to ensure he's not overlooked again next season.