It was an often agonizing year in the NHL, as Ottawa defenseman Erik Karlsson can attest. (Gene J. Puskar/AP)

By John Rolfe

If anyone needed any reminders that hockey players are the toughest customers on the planet, this year provided plenty. Along with the usual avalanche of brutal hits they endured, you had to shudder at the injuries--one nearly fatal--that were truly painful to watch or even contemplate. You can only imagine how the players in question felt, but many of them either continued skating in the game or made it back to action in remarkably short order. So here, if you dare to look, are the 13 most squirm-inducing moments:

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13. Pascal Dupuis pulls out a tooth (10/30/13)

Anyone who dreads going to the dentist and worships at the altar of novocaine likely didn’t enjoy watching the Penguins forward yanking one of his choppers after he was hit in the mouth by teammate Kris Letang’s stick during a game against Boston. Dupuis tried to pull out a second chiclet, but later said he couldn't because it had been "glued" in place. Teammate Sidney Crosby did not appreciate the impromptu procedure, telling Dupuis, "Hurry up, you're grossing me out. Just get rid of it." Of note, John Tavares of the Islanders and Daniel Sedin of the Canucks also engaged in some oral self-surgery during games.

12. George Parros’ fall and concussion (10/1/13)

If you’ve ever fallen and hit your head on ice, you had to feel for Montreal’s enforcer, who landed on his chin during a fight with Toronto’s Colton Orr on Opening Night. Parros, who lay dazed and bleeding, suffered a concussion--remarkably the first of his career, given his role and nine years in the league--and was carted off the ice on a stretcher to spend a day in the hospital. He didn't play again for a month and the incident added fuel to the debate about fighting in hockey.

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11.Jarome Iginla’s wrenched finger (12/14/13)

Iggy, who authored a piece for SI.com about how fighting makes the game better and safer likely didn't do any keyboard work for a while after this mishap. During his first period scrap with Vancouver’s Ryan Kesler, the Bruins forward appeared to jam his left ring finger in his opponent’s visor. The result was a hideously bent digit. Iginla’s reaction strongly suggested that it didn’t feel all that good, but like the warrior he is, he returned to play in the second period.

10. Brent Seabrook's slap shot to the groin (2/17/13)

Any guy who saw this one had to feel queasy. During the first period of a game against the Kings, the Blackhawks blueliner blocked a shot by Drew Doughty that caught him right in what was politely described as "the midsection." Seabrook's return for the start of the second period inspired the Blackhawks to extend their eventual record points streak (from the start of a season) to 15 games with a 3-2 win. "It hurts to look at your teammate and see how much pain they're in when they take a shot like that, but it motivates you and gets everyone into the right frame of mind of what we need to do to win," captain Jonathan Toews said after the game. As Seabrook put it: "Whatever it takes, I guess."

9. Gregory Campbell’s broken leg (6/5/13)

The Bruins forward entered hockey lore during Game 3 of the Eastern Conference Finals when he blocked a slap shot by Pittsburgh’s Evgeni Malkin that fractured his right leg. Campbell gamely rose and hobbled about the ice in obvious pain for another 47 seconds while trying to help Boston kill a penalty. The injury landed him in the hospital for surgery and ended his season, but his fortitude was appreciated by his teammates as well as Bruins fans. "It was a huge play by him," said forward Patrice Bergeron, who knows a thing or three about playing in pain. "That's the way he is. He sacrifices the body always for the team, for the better of the team.” The admirably stoic Campbell later admitted, “It hurt a little bit."

8. Erik Karlsson’s lacerated Achilles (2/13/13)

As the final minute of the second period was winding down, Ottawa's Norris Trophy-winning defenseman was pinned against the boards by Pittsburgh's notorious Matt Cooke, whose skate blade landed on the back of Karlsson's left leg, slicing 70 percent of his Achilles tendon. The photo at the top of this page tells you all you need to know about how Karlsson felt. He was able to skate off, with some assistance, on his good leg. Expected to be sidelined three to four months after undergoing surgery, he almost miraculously returned to the lineup on April 25, having missed 10 weeks and 31 games. His injury caused many players to think about donning cut-proof Kevlar socks, which Karlsson said he will wear for the rest of his career.

7. Eric Staal’s knee injury (5/16/2013

It was a tough year to be a Staal brother. Eric, the Carolina Hurricanes’ captain, was playing for Team Canada in the quarterfinals of the World Championship series in Stockholm when Swedish defenseman Alex Edler nailed him with a nasty knee-on-knee hit. Staal went down in excruciating agony. The severity of his injury was later revealed by doctors who told him he’d sustained a third degree sprain of his MCL as well as small fractures of his right femur and tibia while nearly suffering a clean break. Edler was suspended for the rest of the series. Staal spent two weeks on crutches and was limping and unable to bend his knee for a considerable period.

6. Stephane Robidas’ broken leg (11/29/13)

With 7:26 left to play in the second period, the Dallas Stars backliner was trying to defend against Chicago’s Jonathan Toews when he stumbled and slid hard into the end boards. What made this one so awful to watch, besides Robidas' reaction, was seeing on the replay the awkward bend of his leg as it was fractured. After his surgery, he was expected to be out four to six months.

5.Steven Stamkos’ broken leg (11/11/13)

During the second period of a game against Boston, Tampa Bay’s superstar sniper went down while backchecking at full speed and hit the goalpost, breaking his tibia. Watching what happened to his leg was bad enough, but it was terrible to see Stamkos try to get up only to fall, pound the ice, and writhe. Stretchered off and in need of surgery, he was expected to be out for four-to-six months, yet he was walking on crutches two weeks later and skating at a team practice on December 14 with his eyes on a return to action in February. Don't bet against him.

4. Sidney Crosby's shot to the face (3/30/13)

The concussion history of the NHL's biggest star made this moment even more horrifying. While skating his first shift of a game against the Islanders, Crosby went down like he'd been shot after teammate Brooks Orpik's slapper caught him in the side of his face. Leaving blood and teeth on the ice, Crosby skated off with a broken jaw--an injury many players say is the worst they have ever suffered--and was taken to the hospital where doctors discovered that at least 10 of his teeth had been damaged. Two had been driven back so hard that they cut up the inside of his mouth. (You can read more of the gory details here.) He needed a pair of titanium plates inserted to help his jawbone heal and was out of action until the Pens' second game of the playoffs. He returned with missing teeth, a temporary speech impediment, and a face shield he wore for 10 games before ditching it at the start of the Eastern finals.

3. Patrice Bergeron’s battered body (6/24/13)

Six months later, it still hurts to let your imagination fill in the blanks of the year’s most heroic performance. Bergeron took the ice for Game 6 of the Stanley Cup Final with a cracked rib and torn rib cartilage he’d suffered in Game 5. (If you've ever so much as coughed with a rib injury, you know it feels pretty damn bad. Now imagine taking an elbow or check into the boards with one.) He was able to go after having a nerve block procedure to diminish the pain, but then he separated his shoulder in the first period. Like the Black “It’s only a flesh wound” Knight of Monty Python and the Holy Grail fame, Bergeron soldiered his way through 17:45 of Boston’s season-ending loss and ended up with a punctured lung that put him in the hospital for two days. "I didn't really know all that he was dealing with but I knew he was in a lot of pain," Bruins goalie Tuukka Rask said. "But to see him go out there and battle through it like that with one lung I guess, it's unbelievable and I don't really know how to describe it."

2. Zach Redmond’s thigh gash (2/21/13)

Zach Redmond displayed the wound on his thigh that had been cut by a skate blade.

The tweets from the scene were ghastly. During a practice in Raleigh, NC, Zach Redmond of the Winnipeg Jets had his femoral artery severed by teammate Antti Miettinen's skate and almost bled to death. “I’ve been doing this for 12 years and that’s easily the most-grave incident I’ve been a part of, for sure,” Jets head athletic therapist Rob Milette told the Winnipeg Free Press. “He lost a lot of blood there and his heart was definitely struggling. We were monitoring his vitals, checking his pulse. His pulse was really weak and really slow. He was pale. He was starting to tell us he was getting thirsty and that told us he had lost a lot of blood." Redmond was able to return to practice on April 5, less than two months later--the photo above, tweeted by CBC’s Mitch Peacock, reveals how lucky the rookie defenseman was to have survived--but he did not play again that season.

1. Marc Staal's shot in the eye (3/5/13)

There's something about a gruesome eye injury that makes it almost impossible to think about. During the third period of a game against the Flyers, a hard shot from the blueline by Kimmo Timonen deflected off the stick of Philadelphia’s Jake Voracek and hit the Rangers defenseman in the right eye. The sight of Staal writhing, kicking and bleeding on the ice was unbearable, but what made his injury even more terrible was the uncertainty that ensued. While out for 27 games with an orbital bone fracture and torn retina, Staal wondered if he'd ever be able to see well enough to resume his career. He tried to come back for Game 3 of the Rangers' first round playoff series against Washington, but had to take himself out when his depth perception was off and his eye began to cramp. It wasn't until July that his vision was restored. If any good, besides his recovery, came from the incident it was that it inspired the approval a mandatory visor rule for all players who are coming into the league. Not surprisingly, Staal and his brothers Eric and Jordan, now wear them.