While performing the procedure, Dr. Mark Myerson confirmed a full tear of the left Achilles muscle. Howard also received a PRP (Platelet Rich Plasma) injection, the team said.
Myerson conducted the surgery on Howard's left Achilles which he injured during the last play of Friday's season-ending loss to the Cardinals.
During the play, Howard grounded out and injured his Achilles as he ran out of the batter's box. He limped a few steps and then crumpled to the ground. He was helped off the field as the Cardinals celebrated their NLDS victory.
Howard won't be back to playing baseball anytime soon, according to the team:
"It's going to be five to six months from the surgery until he can play at his accustomed level," said Ruben Amaro, Jr., Senior Vice President & General Manager.
Howard will be immobilized for approximately one to two weeks. He could possibly do weight bearing and strengthening in about a month, depending on how his recovery goes.
"A lot depends on how he recovers," said Amaro. "The start of the season could be impacted, but I still hope he makes his first at-bat of the season."
With the six-month timetable there's no guarantee Howard would be ready for spring training next year.
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