According to Jon Heyman, current Padres starter, Josh Johnson, is set for his third Tommy John surgery, as he recently had a setback on his latest comeback attempt. Johnson hasn't pitched in the big leagues since the 2013 season, and it's fair to wonder if he'll ever make it back at this point.
When his career began, it looked like Johnson would become one of the best pitches in the National League, as he placed fourth in the 2006 Rookie of the Year vote, and in 2010, was fifth for the Cy Young award, and 25th for the MVP. He led MLB with an ERA of 2.30 that season, a mark on which he improved on the following year, as he posted a value of 1.64. Unfortunately his 2011 season was cut short due to injury, but Johnson was able to return in 2012, as he pitched 191.1 innings.
After that season, Johnson was sent north as a part of the blockbuster trade between the Marlins and Blue Jays that included 11 players. He only managed to throw 81.1 innings in 2013 as he dealt with various injuries in his pitching arm. Johnson then signed with the San Diego Padres for a one year deal worth $8 million, however he missed the entire season due a torn UCL which required Tommy John surgery, his second at the time.
According to Jon Roegele there are 66 players that have undergone two Tommy John surgeries, but just two that have had three. That club is comprised of Jason Isringhausen, Jonny Venters, and now Johnson.
If his rehab goes well, and Johnson can prove to be healthy, he'll likely have to return on a minor league deal with incentives. Unfortunately he'll miss the entire 2016 season due to the timing of his surgery, which means that 2017 would be the earliest that Johnson could be back in the big leagues.