In February of 2016, MLB announced that Mets reliever Jenrry Mejia had been permanently banned pursuant to third positive test for banned PEDs. On Friday, the league reversed course and conditionally reinstated Mejia, now 28. 

Here's the full statement from MLB: 

Major League Baseball announced today that Commissioner Robert D. Manfred, Jr. has ruled on New York Mets pitcher Jenrry Mejia's application for reinstatement from his permanent suspension under Major League Baseball's Joint Drug Prevention and Treatment Program (announced on February 12, 2016).  Mejia will be allowed to resume participation in non-public workouts at Mets' facilities following the 2018 All-Star break and will be eligible for a rehabilitation assignment with a Mets' affiliate in mid-August.  Provided that Mejia complies with certain conditions established by the Office of the Commissioner and agreed to by Mejia and the Players Association, Mejia will be reinstated from the Restricted List and will be eligible to resume all baseball activities beginning with 2019 Spring Training.

Commissioner Manfred issued the following statement regarding Mejia's conditional reinstatement:

"Under the terms of our collectively bargained Joint Drug Program, a permanently suspended player like Mr. Mejia has the right to apply to me for discretionary reinstatement after serving a minimum of two years.  Upon receiving Mr. Mejia's application for reinstatement last year, I invited him to New York to meet with me.  During our meeting, Mr. Mejia expressed regret for poor choices he made in the past and assured me that, if reinstated, he would adhere to the terms of the Program going forward.  In light of Mr. Mejia's contrition, his commitment to comply with the Program in the future, and the fact that he will have already spent almost four consecutive years suspended without pay, I have decided to grant Mr. Mejia a final chance to resume his professional career."

Mejia released the following statement through the MLBPA: 

I've had a long, difficult time away from the game to contemplate the mistakes I've made both with regard to my positive drug tests and also the false allegations I made about Major League Baseball's investigation into my testing history. Baseball is my profession, my passion and my life, and for those mistakes I am truly sorry. 

I would like to thank Commissioner Manfred for granting my reinstatement. I would also like to thank my family and friends for their support throughout this difficult period. 

I have much work ahead, but look forward to earning back the trust and respect of the New York Mets, the fans and especially my teammates. 

The usual course of events for PED suspensions is a statement from the player in which accidental/unknowing ingestion of the substance in question is declared followed by acceptance of the penalty. In Mejia's case, though, things didn't proceed that away, which is understandable given the stakes involved. Not long after the ban was announced, Mejia alleged a witch-hunt on the part of the MLB and a lack of support on the part of the Players' Association. Then a few months later, Mejia announced plans to sue the league, and then in January he agreed to a contract with the Mets despite his still being banned. Now, though, there's a clear path toward reinstatement in time for the 2019 season. 

Mejia across parts of five big-league seasons has pitched to a 3.68 ERA/99 ERA+ and a 2.13 K/BB ratio in 113 games, 95 of which were relief appearances. In 2014, he saved 28 games as Mets closer.