The Houston Astros and minor leaguer Jon Singleton agreed on a historic contract Monday, guaranteeing the first baseman $10 million before he has played a single game in the major leagues, a source with knowledge of the deal told Yahoo Sports.

The 22-year-old Singleton, who during spring training called himself a marijuana addict, can make up to $30 million over eight seasons, the first five of which are guaranteed and the final three of which the Astros control with club options.

The improved Astros, who last week won seven straight games, will call up Singleton from Triple-A Oklahoma City and install him as their everyday first baseman after more than a month of negotiations ended in a deal sure to arouse discussion around the sport.

While Rays star Evan Longoria signed his first deal within days of his big league debut, the Singleton contract is the first ever long-term extension for a player with zero major league service time. The Astros’ desire to exchange up-front money for future cost certainty and Singleton’s off-field troubles brought both sides together in hopes of striking a mutually beneficial accord that was made official Monday when he passed a physical.

Singleton told the Associated Press during spring training: “At this point it’s pretty evident to me that I’m a drug addict.” He went on to detail what he called an addiction to marijuana, saying: “I know that I enjoy smoking weed, I enjoy being high and I can't block that out of my mind that I enjoy that. So I have to work against that."

The Astros placed Singleton on their 40-man roster in early October, ostensibly so he would not be subject to the drug tests for minor league players that led to a 50-game suspension for marijuana use to begin the 2013 season. Between the suspension and at least one episode in which Singleton went AWOL and couldn’t be found for days, according to a source, it represented a lost year for Singleton – one from which he has rebounded with aplomb, balancing Houston’s risk with great potential reward.

At Triple-A, Singleton hit .267/.397/.544 with 14 home runs and 43 RBIs in 54 games. He will take over for the Astros’ inert first-base platoon of Jesus Guzman, Marc Krauss and Chris Carter, hoping his left-handed swing can inject some life into one of the American League’s worst offenses.

The lasting impact of the contract goes far beyond whatever immediate effect Singleton has on the Astros. Not only is the deal likely to begin the trend of signing top-end minor league players long term before their debuts, it presents a fascinating case of weighing value now vs. later.

Singleton’s benefit stems from the size of the money guaranteed, the fact it is front-loaded, his receiving it with fewer than 450 Triple-A at-bats and concern over his off-field issues. Just this week he weathered criticisms for tweets in which he mock-insulted a friend by calling him “gay” and said he wouldn’t sign an autograph for a fan “[u]nless you got weed. Aha joke.”

Moreover, the service-time implications had he not signed the deal could have eaten into his potential earnings. The Astros planned on delaying his call-up until after the expected Super 2 cutoff, meaning he would have stood to make less during his pre-free agent years.

Historically, the earning power of solid arbitration-eligible first basemen hasn’t been overwhelming. In his seven seasons leading up to free agency, James Loney made around $16 million. For his six full seasons, Adam LaRoche totaled $16.3 million. While Singleton’s deal could buy out one year of free agency, his under-control years give him a chance to earn $17 million. And Houston guaranteeing $7.5 million through his potential pre-arbitration years, when it could renew him at around $2 million total, adds value as well. If Houston picks up all three options, he would hit free agency at 30 years old.

Should he develop into a star, Singleton could forfeit tens of millions of dollars by locking into the deal. During his pre-free agency years, Prince Fielder totaled $35 million in earnings, and in his first free agent year Detroit paid him $23 million.

Rather than chance it, Singleton opted for the guarantee, aware that $10 million is the sort of fortune rarely given to those in his circumstances. On one hand, he has the sort of money to easily provide for his father, who has been sick. On the other, Singleton knows his fight is not over and that addiction can be a strong and powerful force.

Once he stopped using marijuana, he told the AP, "I went through some slight anxiety, some depression because I wasn't being successful. That was definitely difficult and that drove me to drink." He admitted to "waking up hung over every morning."