SAN FRANCISCO (KGO) — The San Francisco 49ers are advancing to the NFC divisional, but without tight end George Kittle who suffered a torn Achilles during Sunday’s game against the Eagles.

The injury ended Kittle’s season. The recovery will be painful and extensive, something that, according to medical experts, could take anywhere between nine to 12 months before Kittle gets back on the field.

On the field, fans knew something was wrong, and medical experts watched and feared it was his Achilles.

“When you see that they slow-mo on his leg and you see his calf muscle go up and he grabs his leg and see him hit the ground – a lot of the time players know what that is,” said Dr. Nirav Pandya, UCSF Orthopedic surgeon.

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Dr. Pandya specializes in sports medicine. He broke down what Kittle’s medical team is gearing him up for.

“It’s a very painful surgery early on – you are basically going on your ankle, you are sewing these tendons together, immobilizing them, and then you are working through this period of getting that mobility back,” said Dr. Pandya.

According to Nature Review’s research, 30% of sports injuries are Achilles tendon injuries. Dr. Pandya said recovery could be impacted by techniques.

“There are some newer techniques that players like Aaron Rogers who got back in six months, and what is happening in these surgeries is that you are using stronger devices, you are allowing rehab a lot earlier. So, a lot of it will be based on what the surgeon does that he goes, and sees and sometimes you can push that timeline a little bit earlier but for players like him who plays tight end, and sometimes wide receiver, it may take longer because he is stressing that repair a lot more than let’s say a quarterback,” said Dr. Pandya.

Immediately after surgery, Dr. Pandya said patients like Kittle will be placed into physical therapy.

“They will be doing a lot of manual work early on to facilitate the recovering of the tissues and then loading him in the gym,” said Julian Cisneros, physical therapist and owner of Peak Physio.

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Cisneros treats these types of injuries and said it will be almost a year of PT and will happen in phases, with the first one being light resistance.

“It would be light resistance, just trying to go through a full range of motion nice and controlled, slow and steady, making sure his Achilles tolerate that,” said Cisneros.

“Standing under his own body weight on a flat-level surface and raising up those heels nice and high. This would be more load, and once he completes that, we would start elevating him so he can really lengthen that Achilles again and we will give him weights to hold,” said Cisneros. “And then we can start incorporating more plyometric movements with balancing here, and then we will get him on the track or on the field and going through sprints, jumping progressions.”

One of the last phases is to “start incorporating more plyometric movements with balancing,” said Cisneros.

Dr. Pandya is projecting Kittle could be back during the early part of next season, anywhere between September and October.

The good news is that Dr. Pandya says it is very unlikely after full recovery Kittle will re-injure his Achilles.