NHL Players with the Most to Prove at the 2016 World Cup of Hockey

NHL training camps open up later this month, but the best players in the game are already in camps, representing nations and regions for the new World Cup of Hockey tournament.

Excitement is high, even as fans attempt to figure out the vague parts of the tournament such as Team North America. There are also some players attending camp who, despite receiving invites, have questions circling them for the upcoming NHL season.

Questions surround men such as Ryan Nugent-Hopkins—who had an injury-plagued season a year ago—and Marian Hossa—whose offensive numbers are fading—but we should get some answers during the preseason tournament.

Here are nine NHL players with the most to prove at the 2016 World Cup of Hockey and into the 2016-17 NHL season.

Claude Giroux, C, Team Canada

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What he did last year: Claude Giroux led the Philadelphia Flyers in scoring, missing only four games all year. In mid-May, he underwent right hip and bilateral lower abdominal procedures, per CSN Philly. However, the recovery timeline should have him ready for the World Cup of Hockey.

What he has to prove this season: Giroux is one of the league's best centers, but the surgery and recovery mean there are some questions about how long it will take him to get back to 100 percent. He will be 29 in January, and the Flyers need him at full health when the season starts.

What we should watch for at the World Cup of Hockey: Team Canada will be loaded at center, with Sidney Crosby, Jonathan Toews and Ryan Getzlaf in the mix alongside Giroux. His two-way skills should give him a feature role, and this may be a stepping stone for the Olympics in 2018.

Marian Hossa, RW, Team Europe

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What he did last year: Marian Hossa of the Chicago Blackhawks saw his production slip in 2015-16. His point total (33) was the lowest since his rookie season of 1998-99.

What he has to prove this season: Now 37, Hossa is a brilliant power forward with exceptional two-way acumen. He could probably play as a pure checker for several seasons, but the offense faded quite a bit last year. If he is unable to improve his point total, it might represent a real downturn for one of the most impressive players of his generation.

What we should watch for at the World Cup of Hockey: Team Europe is an interesting combination of youth and experience, with Hossa serving as one of the veteran forwards. A mentor role is assured, but it will be interesting to see if he is used as a feature player in the tournament.

Marcus Kruger, C, Team Sweden

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What he did last year: Marcus Kruger of the Chicago Blackhawks was effective in a tough-minutes defensive role last season...when he was healthy. The center lost half the year to a left wrist injury that he suffered just before Christmas 2015.

What he has to prove this season: Kruger needs to prove he can stay healthy. He is a unique player—his defensive-zone starts represented 81 percent of his overall number, according to Hockey-Reference.com—and impossible to replace in that role.

What we should watch for at the World Cup of Hockey: Sweden should be a ridiculous defensive team, with possibly the best group of defenders and three exceptional goalies. In the penalty-killing and checking roles, Kruger should be money.

Andrei Markov, D, Team Russia

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What he did last year: Andrei Markov posted another solid season with the Montreal Canadiens, mostly alongside partner P.K. Subban.

What he has to prove this season: Markov needs to deliver a quality two-way season. He will be 38 in December, and there has been some erosion in his game in recent years. Over the last two seasons, the gap in possession number between Markov with and without Subban widened, per Stats.HockeyAnalysis.com.

What we should watch for at the World Cup of Hockey: The Russian defensive style can sometimes be unusual—it is often based on all five skaters, not just the defense. Markov should thrive for Russia at the World Cup of Hockey and the team will be a pleasure to watch this month.

Auston Matthews, C, Team North America

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What he did last year: Auston Matthews took an unusual route to the NHL draft, choosing to play in the Swiss League, where he flourished at a high level. He led the race for 2016 No. 1 overall pick from wire to wire, with the Toronto Maple Leafs winning the honor of selecting him. 

What he has to prove this season: Matthews will be under pressure to push the Maple Leafs toward the playoffs and finish among the top contenders for the Calder Trophy, which is given annually to the NHL's top rookie.

What we should watch for at the World Cup of Hockey: Matthews is part of a talented group of young players with exceptional offensive talent. Expect North America to be involved in some high-scoring games and Matthews to contribute on offense.

Ryan Nugent-Hopkins, C, Team North America

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What he did last year: Ryan Nugent-Hopkins had a tough season for the Edmonton Oilers in 2015-16. He played in only 55 games and finished with just 34 points—his first time under 50 points in a full year since he arrived in the NHL. 

What he has to prove this season: Nugent-Hopkins needs to provide Edmonton with quality two-way play while young centers Connor McDavid and Leon Draisaitl find their ways. It is a big job, as Nugent-Hopkins will be facing tough opposition and harsh defensive battles.

What we should watch for at the World Cup of Hockey: During 2015-16, he rarely looked comfortable with the puck. A former No. 1 overall selection, Nugent-Hopkins has enormous natural talent and needs to show a combination of offense and defense if Edmonton is to have any hope of making the playoffs.

Tuukka Rask, G, Team Finland

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What he did last year: Tuukka Rask of the Boston Bruins posted an average season—below his established level—in 2015-16. After posting seasons with save percentages of .930 and .922, he fell to .915 last year.

What he has to prove this season: Rask's performance has faded in conjunction with the Bruins' own fade, but there are signs of improvement on this year's roster. Rask will need to improve his own performance in order to justify a substantial salary.

What we should watch for at the World Cup of Hockey: Finland has been dominant in international play over the last 24 months, and it has a real chance to win the World Cup of Hockey. Rask could lead them with a strong performance. Along with Pekka Rinne of the Nashville Predators and Mikko Koskinen, Finland's goaltending will be a big story in the competition.

Tobias Rieder, RW, Team Europe

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What he did last year: Tobias Rieder of the Arizona Coyotes continued to establish himself as a productive two-way forward. His second full year in the NHL saw his point total spike from 21 to 37. 

What he has to prove this season: Rieder is without a contract, and a strong showing this month at the World Cup of Hockey could force Arizona's hand. New York Times contributor Dhiren Mahiban recently tweeted that Rieder will not be in Coyotes camp, partly due to visa problems that come with not having a contract.

What we should watch for at the World Cup of Hockey: Team Europe is an unusual entry into the World Cup of Hockey, but there are some interesting opportunities for instant chemistry. Fellow German Leon Draisaitl has some history with Rieder, and that combination could be effective in the tournament.

James van Riemsdyk, LW, Team USA

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What he did last year: James van Riemsdyk of the Toronto Maple Leafs suffered through a difficult season in 2015-16, missing half of the year due to injury and a difficult rehab, per Nick Kypreos of Sportsnet. 

What he has to prove this season: Van Riemsdyk has to remain healthy. At 27, he should have many productive years ahead. Toronto is an up-and-coming team, and he could be a mentor on a skill line, as well as provide consistent offense. The opportunity to play with Auston Matthews during his rookie season should be a strong incentive for van Riemsdyk.

What we should watch for at the World Cup of Hockey: Team USA will need his offense and experience in the tournament, and van Riemsdyk could be a key player for the club. His slick offensive ability could be vital for a deep run in the tournament.