OWINGS MILLS, Md. -- All you need to know about the determination of Baltimore Ravens general manager Eric DeCosta is in his desk drawer.

About two and a half decades before landing his dream job, he wanted to get into the NFL so badly that he offered to work for free for every team in the league, sending resumes to the likes of Al Davis, George Young and Bill Belichick. He was turned down by all but two teams, and he keeps all 30 rejection letters within arm's reach, just in case he decides to show some youngsters what it takes to overcome disappointment or feels like playfully ribbing a personal idol.

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Not too long ago, DeCosta snapped a picture of a congratulatory note from former Packers GM Ron Wolf next to the rejection letter that he had received from him in 1995.

"Aren't you supposed to be a good evaluator?" DeCosta texted Wolf.

Behind his biting sense of humor and wicked Massachusetts accent is a 48-year-old grinder who has never viewed hardships as setbacks. He considers them challenges.

DeCosta was never the best athlete on the field. He was never the smartest student in the classroom. Give him time, though, and he would outwork everyone. He would find that angle to get an edge.

"I hate to fail," DeCosta said. "I love to win, but I really hate to lose."

At 9 years old, DeCosta didn't make his Little League baseball team. By the time he was 12, he was the best pitcher in the league.

When he started at Colby College, he was an undersized linebacker, a so-called "smurf." By the end of his playing days, DeCosta was the ultra-prepared captain of the Maine school's most successful four-year run in over 30 years who knew everyone else's assignments and wasn't bashful in letting them know, according to his coach, Tom Austin.

When DeCosta joined the Ravens, he was one of the worst racquetball players in the building -- to the point where no one wanted to play him (it simply wasn't a workout), but he quickly became the best. It looked like he would relinquish that title after injuring his right elbow in July. Instead, he learned how to play left-handed and still beat his colleagues.

"He’s the most competitive person I’ve ever met, and I’ve been around really competitive people," said Pat Moriarty, Ravens senior vice president of football administration, who has spent 26 years in the NFL.

DeCosta's competitive streak has proved to be as long as the titles he has held in Baltimore. After he joined the Ravens a few months after their relocation from Cleveland, his ascension went like this: pro personnel assistant (1996-97), Midwest scout (1998-2002), director of college scouting (2003-2011), assistant general manager (2012-17) to the second person to command the franchise's personnel department.

The right-hand man of Ozzie Newsome, DeCosta played a key role in building the 2012 Super Bowl championship team and drafting 11 Pro Bowl players, including Terrell Suggs, Haloti Ngata, Marshal Yanda and Ray Rice, since becoming the NFL's youngest director of college scouting in 2003.

DeCosta was first approached by owner Steve Bisciotti about taking over as Ravens GM in 2007, and he chose to remain with the organization despite many tempting offers. Over the previous nine offseasons, DeCosta reportedly turned down nine teams when they sought permission to speak to him.

Eric DeCosta couldn't imagine being a GM anywhere that wasn't Baltimore. Courtesy of Baltimore Ravens

He declined an interview with Seattle even after getting a phone call from then-Seahawks owner and Microsoft co-founder Paul Allen. He also passed on meeting with the Packers even though Bisciotti himself called the GM job there "the best job in the NFL."

Only one current NFL general manager has been with his team longer than DeCosta and that's Cowboys owner Jerry Jones. Those closest to DeCosta, including Jaguars GM Dave Caldwell, his tightest friend in league circles, were not surprised at how he bided his time in Baltimore.

"If you know the person, you know what is important to him," Caldwell said. "It’s very admirable for him to stay there and see it out. Here is a guy who could’ve left for any job over the last 10 years. To climb that ladder is very unique. It shows his character and what he’s made of."

Annoying little brother

From his earliest memories, DeCosta knew he wanted to become a general manager. He'd spread out his baseball card collection and build teams.

So, why did DeCosta decided to stay in Baltimore instead of jumping at the chance to run another organization?

DeCosta will tell you that he couldn't uproot his wife from her hometown. What it really boiled down to was DeCosta, a kid who grew up a half-hour drive from Patriots games and long rooted for the Cowboys, had found his football home in Baltimore.

He thinks of his coworkers as family, and the feeling is reciprocal. Well, sort of.

"He really is that annoying little brother that I never had," Moriarty said.

DeCosta is known for pulling pranks, annoying those inside the Ravens' facility relentlessly. Pictures on desks will strangely get switched from office to office. Newsome's cellphone will mysteriously be changed to a different language. Reporters doing TV shots outside will have to wait while countless car alarms curiously go off at the same time.

No one feels the brunt of DeCosta's mischievous side more than Moriarty, the godfather to DeCosta's youngest son.

Moriarty doesn't know what to say when someone asks, "How much for your car?" That's what happens when someone places a "For Sale" sign on the inside of your windshield.

The Ravens' security guards know to get out the master key when Moriarty is headed their way. Once again, someone locked him out of his office.

If it's Valentine's Day or St. Patrick's Day, an email will be sent out to the entire organization (including the owner) from Moriarty if he doesn't lock his computer. It will typically read, "I look forward to celebrating this holiday with my family, which I love dearly, and I hope you love your families dearly, and enjoy the spirit of the holiday."

The best prank came when Moriarty's long-awaited Cole Haan black loafers were delivered to the facility. Moriarty opened the package only to find already-worn shoes. In fact, they were the same pair he had for years. DeCosta pried open the box from the bottom, taking out the new shoes and replacing them with ones from Moriarty's locker.

DeCosta: Wow, those are a really nice pair of loafers.

Moriarty: No, these are my shoes.

DeCosta: Yes, I know they are your shoes. You just bought them.

Moriarty: No, you don't understand. These are my shoes!

There has been one common thread to DeCosta's trickery.

"He has never admitted to anything," Moriarty said. "To this day, it has never been him."

The cable guy

DeCosta's NFL career got jump-started in a bar in Hartford, Connecticut. A graduate assistant coaching at Trinity College, DeCosta happened to strike up a conversation with someone who just had an internship with the Washington Redskins.

It was an epiphany for DeCosta, who immediately left to work on his resume and send letters to NFL teams.

Hired for the summer by the Redskins, DeCosta helped organize the team's first training camp at Frostburg State, delivering refrigerators, mattresses and TVs up the stairs of dorms. He even went room to room hooking up the boxes for cable TV.

"It was great because if it didn't work out for me in scouting," DeCosta said, "I could always go work at Comcast."

The next year, DeCosta was in the running for a player personnel assistant role with the Ravens, his first full-time job in the NFL. The other finalist was Paul DePodesta, who later became the Los Angeles Dodgers general manager and is now the chief strategy officer of the Cleveland Browns.

Eric DeCosta is known as quite the prankster around the Ravens' facility. Courtesy of Baltimore Ravens

What worked in DeCosta's favor was his far-from-privileged background.

"A couple of guys I knew from Taunton [Massachusetts] were salt of the earth, hard working, tough achievers," said Scott Pioli, the Falcons assistant GM who hired DeCosta when he was with the Ravens. "In the short time I spent with Eric, all of that came true."

On the day the Ravens offered the position to DeCosta, he learned he got wait-listed into the University of Connecticut Law School. The decision boiled down to pursuing a degree or a dream.

"I didn't look at it as a risk; I looked at it as a chance to see where it would take me," DeCosta said. "I felt once I got down here, I would impress people. I was confident in my abilities, and I knew I could do it."

From that point, everywhere you looked, DeCosta was there. When you saw Ted Marchibroda, there was DeCosta wearing the headset on the sidelines for the old-school coach or driving Marchibroda's car for an oil change. When you met with Newsome, there was DeCosta with his trusty trade value chart.

"It's like he's always been there," Moriarty said. "He was a source of information. They used him as a sounding board almost immediately."

Moriarty added, "When Ray Lewis walked onto camp his first day, he never really was truly a rookie. He was Ray Lewis, our starting linebacker. I think Eric was never Eric the intern. He was more than a scout."

Succeeding a legend

If Newsome wasn't already in the Pro Football Hall of Fame as a player, he presumably would be in Canton after being the architect for two Super Bowl championship teams.

DeCosta has no intentions of filling Newsome's shoes.

"I have size 10½ feet and I think Ozzie is a 13, so there you go," DeCosta quipped.

Newsome remains with the team in a non-titled advisory role, but DeCosta is the final decision-maker. In his first major move, DeCosta traded former Super Bowl MVP quarterback Joe Flacco to the Denver Broncos for a fourth-round pick even though no other team was publicly vying for him. In March, DeCosta excruciatingly watched four key members of the NFL's top-ranked defense leave on the first day of free agency before adding safety Earl Thomas and running back Mark Ingram.

DeCosta has made it clear that he wants the Ravens to be more financially responsible with the salary cap, re-sign their young talent before they land lucrative deals in free agency and rely more on cutting-edge technology than his predecessor.

"He has the ability to see the big picture, which is essential as a general manager," said Charley Casserly, the NFL Network analyst who hired DeCosta in 1995 when he was the Redskins GM. "A lot of scouts don’t have that ability."

DeCosta is closing in on his first draft and the pressure is on. How much does DeCosta enjoy this time of the year? A few years ago, DeCosta tore his Achilles while playing racquetball at the Ravens' facility right before a pre-draft meeting. He quickly grabbed a bucket of ice for his foot and showed up 15 minutes late.

"As a kid, I loved to play Risk, I loved to play Monopoly -- all those games," DeCosta said. "To me, [the draft] is a game, but it’s not a game we can afford to lose."

It was 25 years ago when one of DeCosta's first jobs with the Ravens was to drive players back and forth from the airport for their pre-draft visits. Now, DeCosta finds himself in a different driver's seat in the organization.

In the NFL, no one understands how much patience and persistence pay off more than DeCosta.

"Did I have chances to go elsewhere? Yeah. Did I have a lot? Yeah. Did I ever really consider it? Not really," DeCosta said. "Every time I'd go to bed, thinking that maybe I would consider something, I'd wake up and say, 'What are you, crazy? You know you're going to have the job someday that you've dreamed about, so just wait and make it perfect.'"