Darrius Barnes knew something was wrong when he felt a twinge in his knee during an April 11, 2015 game at Gillette Stadium. The New England Revolution defender had successfully warded off lingering knee problems for the last several seasons, but this tweak was different, and the ensuing swelling served as a gloomy omen. Scans later revealed the 28-year-old had torn the patellar tendon in his left knee. Corrective surgery would place him on the disabled list for six months, effectively ending his season.

Tales such as Barnes’ are all too common in Major League Soccer, as players see a bright spell of form prematurely halted by a season-ending injury. More often than not, players and trainers alike recognize the pain is far more than a measly bruise or knock. Instead, it’s something physically and mentally crushing.

“It’s tough to get over that initial shock, for sure,” Conor Casey, a striker for the Philadelphia Union who has torn his anterior crucial ligament twice and Achilles tendon once, said. “That’s the first step, getting over the physical pain and wrapping your head around that you’re in for the long haul and going to have to be patient.

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“That’s really the hardest part, especially early on when you’re still on crutches and not really back in terms of doing rehab stuff,” Casey added. “Knowing you have anywhere from six months to a year before you’re back playing, it’s tough.”

While modern medicine and top-notch doctors ease the physical pain, the toll on one’s body cannot be understated, especially if a player has encountered such misfortunes before. The crushing blow often makes a player question whether or not their body will be the same again.

For Ike Opara, his most recent injury — a ruptured Achilles tendon in his left ankle — even caused the possibility of retirement to creep in. After all, the Sporting Kansas City defender has battled long-term injuries throughout his career, and there becomes a point when athletic aspirations are placed on the back burner in place of comfort later in life.

“There was uncertainty, to say the least, with where my career was headed and what I wanted to do,” Opara said. “Then obviously whether soccer was going to be it or not.

“But more importantly, my main goal was just to get healthy for the rest of my life because at some point or another I need to be healthy,” Opara added. “That’s kind of how I attacked the recovery, at least early on, was to make sure that when I’m 40 I can function and walk and do all the necessary things to lead a good life.”

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As Opara alluded to, the mental battles are often the most difficult aspect of a long-term injury. Timeframes can be conquered, but the internal demons of doubt are not so easily quelled.

Players are accustomed to their routine of practice, gym sessions, film meetings and other preparation for the upcoming weekend’s game. Yet, through one torn knee ligament or serious concussion, doctor’s appointments and physical therapy become the new norm.

“You go through periods sometimes around the initial shock where you wonder if it’s it and if you’re going to get back to the same player or if it’s going to linger forever,” Casey said. “The mental part is for sure a lot more difficult than the physical part. A lot of it is just a mind game of convincing yourself that even if you don’t feel great, you’re getting close and have to keep chipping away at it.”

Despite the debilitating nature of long-term injuries, there are positive elements that lessen the impact of months on the sideline. Watching away games on the television and home games from the stands, players often gain perspective about ways they can better themselves. Due to their competitive nature, players naturally long to be back on the field, but lessons big and small are valuable nonetheless.

“When you’re coming in doing the same thing day in and day out with the same exercises, it’s mentally tiring and fatiguing,” Barnes said. “You have to think of the end product, which is to be on the field again. In the five or six months, I was able to watch the game from a different perspective, just seeing the little things and where I could improve my game. I wasn’t playing, but I learned a lot of what I could do differently.”

Support from the club and family members also aid the fight back from injury. Teammates understand what each other are going through and loved ones help one navigate the darkest of moments. Strong relationships become invaluable as they provide support through a taxing period of life.

The most important relationship often lies with the club’s medical staff, though. They work individually with the player to get their body back to peak condition, all with an astute focus on little aches or pains.

For Cameron Porter, a forward for the Montreal Impact, this phenomenon overwhelmingly resonated after he tore his the anterior crucial ligament in his left knee in March 2015.

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“The person I worked with the most is Sheehan McBride, one of our therapists here in Montreal,” Porter said. “He has just such an incredible interest and dedication in everything related to my knee. Spending extra time working out any little pain I would have and figuring out how it could be caused, even if it’s from some obscure item in another part of my body.

“I owe a lot of it to his dedication and helping me understand how my body was working and how I was going to heal,” Porter added. “I like that knowledge. All I can do is put in the hard work and determination, and it’s up to them to really give me the tools to succeed. I’d have to thank him a lot for that.”

With the highs and lows in mind, the biggest driving force for an injured player is the light at the end of the tunnel. There must be an end goal, because without it the journey back to health is for naught.

Throughout the process, days riddled with steps in the right direction are inevitable, but so are ones where a full recovery seems no more than a flickering hope. However, finding a happy medium and staying true to the doctor’s plan can ease the pain of dubious thoughts.

In doing just that, the long-term injury eventually becomes nothing but a conquered obstacle. Most importantly, though, hard work and dedication results in an indescribable moment: when one returns to the field. Whether it’s a stoppage time substitute appearance or full 90-minute performance, the return to action is emotional for all parties involved.

“It’s going to be overwhelming,” Opara said of the moment he’ll play once more for Peter Vermes’ side. “The support I’ve gotten from family and friends has been unreal, so it’ll be for everyone who has helped me along. I think that’s kind of the joy behind it. They all feel some sort of investment in my well being, as they should. Everyone who has played a part will be ecstatic, as will I.”

Season-ending injuries are full of ebbs and flows, but the journey back is something that even the most eloquently spoken struggle to put into words. In one moment, the yoke of crutches and braces become a thing of the past, and love for the game returns.

“When I think about the process as a whole, it’s kind of like going on a long journey driving a car through the night,” Porter said. “You know where you want to get, you have the headlights on and at any one time you can only see a few feet forward. But, at the end, you’ll be pulling up to that hotel or wherever it is, and you realize the relief of the journey. The moment I’m back is going to be unbelievable.”