The 2019-20 rookie class is defined by defensemen. While Cale Makar and Quinn Hughes have put up big numbers, there is another pair of blueliners within our top six who deserve recognition, and they're a pair of guys you could have seen play together in the past.

Rangers defenseman Adam Fox and Penguins blueliner John Marino spent the past three NCAA seasons patrolling the blue line at Harvard. Fox was initially drafted by the Flames but later flipped first to the Hurricanes and then to the Rangers. Instead of returning to Harvard for his senior season, he signed with New York and played a significant role as a key building block in their restructuring. Marino, meanwhile, was perhaps the even bigger surprise to leave the Crimson. Originally drafted by the Oilers in 2015, Marino was flipped to the Penguins for a conditional 2021 pick in late July.

Fox was the flashy offensive defenseman who led Harvard in scoring and was one of the final three Hobey Baker finalists last season. His production made him the big name. Marino, was right behind him on the depth chart but made a much bigger defensive impact for the team. Marino's career high in points with the Crimson was 16 in his sophomore season.

Their similar paths have now led into pretty solid first seasons in the NHL. While they might not get the recognition of Hughes and Makar, each of whom also came from the college ranks, they've become key pieces for their teams' present and future. Here are the top 10 rookies so far this season. All statistics cited are from NHL.com, hockey-reference.com and Natural Stattrick and current through Jan. 5.

1. Cale Makar, D, Colorado Avalanche

Previous ranking: 1

Despite missing a significant chunk of time because of injury, Makar remains only three points off of Victor Olofsson's scoring total. He still leads all rookies in points per game and has returned to Colorado's lineup as its top defenseman without missing a beat. He deserves a long look as the All-Star Game's last man in for the Central Division because he's undoubtedly a huge part of Colorado's success so far this season.

2. Quinn Hughes, D, Vancouver Canucks

Previous ranking: 2

Hughes is becoming one of the NHL's most effective transition defensemen. His ability to collect pucks and get the Canucks going the other direction is unique. Even the way he scoops pucks off the boards is different, and his feet still leave forecheckers bewildered with which direction he's going to go. No rookie is playing more minutes per game. Meanwhile, his relative Corsi for percentage is 6.9%, which is right near the top of the rookie class. He has made an especially positive impact on the Canucks this season and has far exceeded any expectations I could have had for him, even as a prospect I've thought so highly of for years.

3. Victor Olofsson, LW, Buffalo Sabres

Previous ranking: 3

The rookie of the month for December, Olofsson continues to produce at a solid rate. He leads all rookies with 35 points and is second in points per game. Meanwhile, he is averaging nearly three minutes more ice time per game than any other rookie forward. And for as much of a power-play performer as he was early in the season, he's second among all rookies with 21 even-strength points. Unfortunately, the Sabres just lost Olofsson (lower-body injury) for six weeks.

4. Adam Fox, D, New York Rangers

Previous ranking: 5

Averaging over half a point per game and getting top-four minutes on a nightly basis, Fox has exceeded Year 1 expectations. He has shown a level of poise with the puck that was always evident in lower levels, and his average north-south speed has not been an issue thanks to good edges and anticipation. He has helped the Rangers in the puck-possession game with a 6.2 relative Corsi for, which is tops among rookies. Fox moves the puck remarkably well, racking up assists and aiding in the transition game. His move from college to the NHL has gone better than I anticipated, especially in a difficult situation with the rebuilding Rangers.

5. Nick Suzuki, RW, Montreal Canadiens

Previous ranking: 9

Suzuki is flourishing as his rookie season progresses. He has given Claude Julien, a coach who notoriously has a short leash for younger players, no choice but to play him. Montreal's injury issues might have helped a bit, but Suzuki has made the most of his time as a consistent top-six forward and power-play option. Suzuki had a seven-point week to close out December and played a career-high 20:43 in his first game of January. He's trending up quickly.

6. John Marino, D, Pittsburgh Penguins

Previous ranking: 8

I'd be lying if I said I saw this coming. Marino has already passed his single-season point total for any of the three years he played at Harvard in his first NHL campaign, and he's playing a top-four role for one of the league's prestige teams. Marino is one of only four rookie defensemen averaging over 20 minutes per game and is seventh among all rookies with 15 even-strength points.

7. Martin Necas, C/W, Carolina Hurricanes

Previous ranking: 7

He's a bottom-six player on a really good squad, but I think most teams would love to see a bottom-six guy produce the way Necas has as a rookie. The Czech forward has settled in on the wing on Carolina's third line with Erik Haula and Ryan Dzingel. Necas is tied for fourth among all rookies with 23 points (18 at even strength) but is second among all rookies with 2.22 points per 60 minutes.

8. Ethan Bear, D, Edmonton Oilers

Previous ranking: 6

Of the rookies in the NHL, few are drawing tougher assignments than Bear. And yet the Oilers are controlling shot attempts at a rate 4.7% higher with Bear on the ice than off. He's second only to Darnell Nurse among Oilers defensemen in average time on ice, he starts over half his shifts in the defensive zone and he is a largely reliable defenseman on a team that has been relatively leaky.

9. Ilya Mikheyev, LW, Toronto Maple Leafs

Previous ranking: 4

It might be a while before we again see Mikheyev on the rookie rankings after that scary laceration he suffered just over a week ago. He really seemed to be clicking with John Tavares too. The 25-year-old was tied for fourth among all rookies with 23 points when he went down. Mikheyev was getting solid middle-six minutes and scored almost exclusively at even strength, leading all rookies with 22 even-strength points before the injury. Now out three months, Mikheyev will get passed, but he has been an extremely valuable member of the Maple Leafs to this point.

10. Ilya Samsonov, G, Washington Capitals

Previous ranking: NR

Samsonov has appeared in only 15 games so far but has been a factor. With a .918 save percentage, Samsonov has won 11 of 13 starts, including all eight of his starts on the road. He is only the second goalie in NHL history to win each of his first eight starts away from home. The Capitals have a good situation with their young netminder as Braden Holtby's contract situation beyond this season remains unclear. While I think this rookie class has a lot of players who could fit in this spot, you have to recognize what Samsonov has done even in a limited role.