What defines a great NHL defenseman?

That's a question fans, pundits, executives and players themselves have debated for decades.

"The problem with defensemen is you can go one of two ways. You can go with the guy who puts points on the board, or you can go with the guy who is defensively responsible," one NHL coach told ESPN. "I value those [defensive] guys way more than the guy who puts up 80 points a year and is not as good defensively."

Others might argue the value of dominant point-producing blueliners can't be overstated, and that the best defense can be a good offense.

Finding a defenseman who offers elite play in all three zones separates the franchise players from the stars -- and, in some cases, the top players in our expert ranking of defensemen from the rest of the list.

ESPN's 2023 NHL position-by-position ranking collected 20 surveys that represented those on the ice and behind the scenes.

Here's how it worked: Surveys were conducted over the past two months. Respondents were asked to rank their current top 10 players at center, winger, defenseman and goaltender, based on a predetermined list of the top 25 to 35 players at each position. Players who were ranked in the top 10 on each ballot were given a numerical score -- No. 1 earned 10 points, No. 2 earned nine points and so on.

There were 10 NHL players surveyed -- six from the Eastern Conference, four from the Western Conference. They range from NHL award nominees to veteran role players. To balance that perspective, we surveyed 10 people from the hockey operations departments of NHL teams, including three coaches and three general managers.

Combined, their insights led to rankings that go behind fan conjecture and media narratives to reveal the best of the best -- at least according to those inside the NHL.

Here are the top 10 defensemen, according to our surveys, with additional reporting from yours truly, Kristen Shilton and Ryan S. Clark to add context to the choices. Stats are collected from sites such as Natural Stat Trick, Hockey Reference and Evolving Hockey.