Boston Celtics guard Marcus Smart expressed fear that he was going to lose his eyesight after experiencing viral conjunctivitis that caused an infection in both of his eyes.

Smart is nearing a return to the court after missing seven games with the infection and told ESPN on Wednesday that he is about 80 percent healthy. But, he said, there was a time in which he was getting nervous.

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“Hell. I thought I was going to go blind for a while,” Smart told ESPN before Wednesday’s game against the Toronto Raptors, which he also missed. “I think it was the worst case of viral conjunctivitis that they've seen. So, basically, I was a guinea pig to see how to handle this if it ever happens again to anybody else.”

Smart described in great detail dealing with immense pain in his eyes.

“So it was painful, it was burning ... it was really hard,” he said. “I couldn't see. I had outdoor sunglasses everywhere. Even in the dark, I was wearing sunglasses. It was that bad. Just every morning I would wake up just having sticky discharge coming out of my eyes, sealing my eyes shut. It was really just gross. It got so bad that my eyes, my eyelids started forming these mucous membranes, and they literally had to go in and pry the mucous membranes out.

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“I actually have a picture that I showed the guys. It was pretty gross. I was bleeding tears every time they did it, for like a day. They did that for about four days straight. The first day was probably the worst, just because it built up so much that it started to scab under my eyelids, and they had to open the scab and then pull it out. It felt like they were putting needles in my eyes. They were using tweezers and vise grips to hold my eyes and actually get into my eyelids, the bottom and top.”

Smart said there were legitimate concerns about his eyesight.

“They were so worried about it infecting my cornea and my vision, so it was really scary,” he told ESPN. “At first we thought it was an allergic reaction because I broke out in hives like the day before my eyes started having an allergic reaction. We caught it so early, the same symptoms came out. Then about three days later it transferred from my left eye to my right eye, and that's when we ruled out that an allergic reaction was the cause. They said it was a virus. ... It was caused by having a cold already and being sick.”

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Smart has not appeared in a game since Dec. 6. He said his eyes are feeling better and that he’s at “80 percent” game-ready wise.

In 20 games this season, Smart is averaging 11.8 points and 3.4 rebounds per game.