Being a professional athlete is a desirable life on paper. The best at their professions are paid millions upon millions of dollars to play games in front of what can, at times, be adoring fans, crowds that shower winning athletes with praise. Those who participate in leagues that offer guaranteed contracts are able to rest easy and know that they will be financially secure for the rest of their lives, even if their playing careers were to suddenly and unexpectedly flame out. Perhaps best of all is that successful pro athletes are able to retire before they turn 40 years old.

As is often the case with all varieties of life, it's not always sunshine and puppy dogs for pro athletes. Fans have high and sometimes unrealistic expectations for the players that they follow, and the pressure that comes with that reality can beat down even the strongest of personalities. Then there is the criticism that comes from coaches and from television and radio show hosts, the boos and jeers from fans that once cheered an athlete on, and also the nagging injuries and fatigue that can sideline a player or even stop what was once a budding sports career right in its tracks.

Sometimes, it all just becomes too much to handle. Athletes, like anybody looking to ease physical and/or emotional pain, have been known to self-medicate and use substances such as alcohol or narcotics, and just like anybody else, some athletes become dependent on those drugs. A stint in rehab can save a career before it spirals out of control, while other athletes find that they have to complete multiple rehab runs in order to avoid a heartbreaking end to their personal tales. This list begins with a young man who is hopefully getting his life in order in the early days of his pro career.

10. Johnny Manziel - Alcohol Dependency

His “Johnny Football” days now memories and not much more, Manziel entered a rehab program, reportedly because he was worried about having an alcohol dependency, following what was one of the more disastrous National Football League rookie campaigns in recent memory. What Manziel will or will not be as an NFL quarterback is not yet known despite the fact that plenty of people out there have opinions on the hoped-to-be savior of the Browns. Manziel first has other things to work out, and the hope is that he can get his personal life figured out before he begins training camp later on in 2015.

9. John Daly - Alcohol Dependency

A FOX Sports report that was released in June of 2014 showed just how wild the career of the golfer who once sang about how he “Hit it hard, man” has been over the years. According to that report, John Daly has been ordered to attend counseling or alcohol rehab up to seven times. Daly has not been shy about talking about his issues with alcohol and gambling during media events. The man once known primarily for his ability to hit long drives and who will turn 49 years old this coming April draws attention whenever he jumps out to an early lead at a tournament. Maybe, just maybe, “Long John” has one more big win left in him.

8. Darryl Strawberry - Cocaine Addiction

Darryl Strawberry seemed to be on the verge of greatness in the 1980s. He won the 1983 National League Rookie of the Year Award, and he was part of that 1986 New York Mets side that shocked the Boston Red Sox in the final two games of that year's World Series. Strawberry's much-publicized bouts with cocaine addiction and other demons cost him years of what could have been a historic career, and he had multiple stints in treatment centers. The man who enjoyed a successful comeback run with the New York Yankees has gotten his life in order, and he went on to found the Darryl Strawberry Recovery Center.

7. Jordin Tootoo - Alcohol Dependency

The first Inuk player to participate in a National Hockey League regular season game wrote in his book about when he hit rock-bottom in 2010:

David Poile had heard all of that too many times before, and he wasn’t buying it anymore. He gave me an ultimatum. He said:

“If you don’t accept what we’re offering you, we’ve got to let you go. You’re damaging our team. You have to enter the NHLPA substance abuse program and go into rehab or we’re going to cut you, and everyone will know why.”

Tootoo has claimed that he has not since had a drink of alcohol.

6. Chris Herren - Heroine Addiction

Herren played professionally in the National Basketball Association and overseas through seven years, and he battled with drug addiction for over a decade of his life. Things got so bad, according to Herren, that he chose to shoot heroin before his own mother's funeral, and he once had to be brought back to life after an accident that was caused by an overdose. Herren thankfully got his life in order, and he went to form Hoop Dreams with Chris Herren. The ESPN documentary about his career and his recovery from addiction, Unguarded, received two Emmy nominations, and Sports Illustrated named it the Best Documentary for 2011.

5. Dwight Gooden - Alcohol and Cocaine Addiction

Gooden, like Strawberry, was part of what should have been the glory years of the New York Mets franchise. Also like Strawberry, Gooden shaved years off of his own career and also lost millions of dollars in the process because of his addictions. Their lives followed similar paths in that Gooden also struggled to turn things around once he was out of Big League baseball. The former “Dr. K.” has written about his battles, which included Gooden going on VH1 reality television program Celebrity Rehab With Dr. Drew. Gooden has remained clean, and he now shares his story with others.

4. Paul Gascoigne - Alcohol Dependency

Gazza, as he has been known since his glory days at Tottenham Hotspur, has publicly battled alcoholism and mental illness since the middle of his career. Gascoigne has received treatment overseas and in the United States, repeatedly relapsing after it had appeared as if he had finally conquered his demons. Gazza was put on a three-day detox in October of 2014 following what the press referred to as a “drinking binge.” He is, as of February 2015, eying a return to the game that he loves as a television pundit. While it is a shame that we will never know how great Gascoigne could have been as a footballer, it is his health that is most important.

3. Josh Hamilton - Alcohol and Cocaine Addiction

Hamilton was a top-tier baseball prospect when a car accident that occurred in the spring of 2001 forever changed his life. It was then that he began using alcohol and cocaine, and it was not until 2007 when Hamilton finally began to flash his greatness on the field. Hamilton serves as a reminder that addiction is a true disease that cannot be fully cured, as the 2010 American League Batting Champion, 2010 AL Most Valuable Player and 2010 AL Championship Series Most Valuable Player has suffered relapses on multiple occasions. He could miss the start of the 2015 regular season after undergoing shoulder surgery.

2. Brett Favre - Addiction to Painkillers

The all-time great Green Bay Packers quarterback was known for his partying ways while he was with the Atlanta Falcons, but it was an addiction to painkillers that led Favre to enter the NFL's substance-abuse program in the spring of 1996. Favre followed that tumultuous offseason by helping guide the Packers to the Super Bowl, winning regular season Most Valuable Player honors in the process. The rest, as the saying goes, is history. Favre is widely regarded as one of the greatest quarterbacks to ever play the position, and he will be inducted in the Pro Football Hall of Fame when he is first eligible.

1. Lawrence Taylor - Cocaine Addiction

There are some knowledgeable football individuals who believe that L.T. is the greatest overall player in the history of the National Football League. He has also, over the years, been a troubled soul, one who first entered a drug-rehabilitation program in 1986. Taylor's struggles with substance abuse continued on through and after what was a Hall-of-Fame career. Go and find highlights of Taylor in his prime when he was a defensive player for the ages, and then consider this: Taylor could have been even better than he was had he taken those rehab stints seriously, kicked bad habits and gone all-in on his football career.