The American suffered a freak right knee injury during her clash against Sorana Cirstea today that left SW19 fans feeling sick.
Mattek-Sands, 32, fell to the ground and yelped “f**k, help me, help me” while clutching her leg early in the third set.
Cirstea jumped over the net and gasped as her stricken opponent was sprawled on the deck.
Speaking for the first time about the incident, Cirstea said: “I think the kneecap, it was out.
“I’m not a doctor, I’m not a specialist. I’ve never seen anything like this, but it wasn’t in a normal position.
“That’s why I kind of freaked out because I’ve never seen this. I spoke with my physio afterwards, if he knows a little bit more.
“Hopefully it’s not as bad as it seems. Hopefully she won’t need surgery or something like this.”
Fans shielded their mouths in horror at what they were seeing as Mattek-Sands squirmed on the ground.
Medics swiftly came to her side and spent 25 minutes treating her as husband Justin and her doubles partner Lucie Safarova rushed to help.
The pair have won the last three Grand Slam titles at the US Open, Australian Open and French Open. They had been hoping to complete the full set at the All England Club.
Mattek-Sands had won the first set 6-4 and lost the second on a tie-break moments before the fall occurred.
The All-England Club released a statement after the incident which read: “The first response to Court 17 was within 1 minute, by a qualified ambulance technician.
“The player was kept on court while pain relief was given.
“The player was then transferred directly to an ambulance and taken under emergency conditions to a hospital.”
“I said ‘I’m here, I’m here, I’m here’. I think was tough because she was stuck on this, Sorana, help me, Sorana, help me.
“I said ‘I am here, you are strong, you can do this’.
“I was trying, but of course I felt useless. In this kind of moment when she was screaming so loud, you watch the knee, it was a very uncomfortable moment.
Tennis legends past and present rushed to Twitter to send Mattek-Sands their best wishes as news of the incident broke.
Marion Bartoli posted a picture of Mattek-Sands holding two trophies and said: “That s how I love to see u love, holding a trophy with @luciesafarova and smiling and you will be back soon there!! All my love to u champ.”
Former Wimbledon finalist Sabine Lisicki said: “Omg no no no This is so heartbreaking.”
While former Grand Slam champion Sara Errani added: “I have no words… be strong I send all my energy to you.”
He said: “It must have been an hour since it happened and I’m still shaken up now.
“She was on the ground, clearly in agony, and it seemed like an age before anyone actually came to help.
“I saw her knee just buckle and as soon as she started shouting I nearly threw up.
“She was shouting “help, help, help” but for a moment it was almost as if no-one knew what to do.
“She settled down eventually but it was really pretty brutal to watch.
“I didn’t know who she was before today. I just came to watch the final set as I saw it had come into a decider and you don’t expect to see something like that.
“I just hope she’s alright.”
