It's only been a day since Joe Flacco went down, and fans are already anxiously awaiting his return amidst the coping process. But there's one problem with this. We really don't know when that will be.

While the details are scarce at the moment, we know for sure that Flacco has torn his ACL and MCL. Our own Dr. Robert Esbrandt believes that he likely has a medical meniscus tear as well.

@sgellison If ACL and MCL are both torn he likely has a medial meniscus tear as well — Bobby Esbrandt (@DrBobbyE) November 22, 2015

Once Flacco has his MRI done today, we'll better know the full extent of the injuries and can create a more narrow timetable for his return.

So what does this all mean? And what is the timetable for his return?

First, let's start out by defining these ligaments and what their purposes are. We commonly mention these acronyms and don't actually know the meaning of them.

The ACL, or anterior cruciate ligament is the most common knee ligament to be injured. The ACL is responsible for the prevention of hyperextension, stabilization of the knee, controls rotation of the tibia on the femur, and is ultimately considered the most important ligament in the leg. When the ACL is torn, it unravels like a braided rope. Injuries of the ACL can actually occur in both contact and non-contact situations.

In athletics, patients almost always receive surgery. This surgery is accompanied by aggressive therapy, meant to restrengthen the knee. The typical recovery time for your average is athlete is somewhere around six to nine months. Almost all athletes return at or near their previous level of play, and the reinjury risk is surprisingly low, between 5 and 15 percent according to Brown University.

Thanks to advances in modern medicine, the previously career-threatening ACL injury is now just a year-long setback. Surgeries are overwhelmingly successful, and when coupled with state-of-the-art sports medicine, players can be back on the field faster than ever.

The ACL's neighbor, the MCL, or medial collateral ligament, also serves a key purpose. It is responsible for stabilizing your knee joint and preventing it from buckling inwards. Players whose knees twist at awkward angles (like Le'Veon Bell recently) often sustain MCL injuries. While not as common as ACL injuries, MCL injuries also occur at high rates within contact sports. The ligament can be injured when an outside force is applied just above the knee, or when the knee is twisted at a very obtuse or acute angle.

The recovery time for a MCL injury is very much dependent of the grade the injury is. Grades I and II often mean a break of about a month or two from physical activity. These athletes would receive a treatment known as RICE. That's rest, ice, compression, and elevation. Grade I and II sprains are categorized either ligament stretches or partial tears. It is likely that Flacco did not sustain this injury, but rather a Grade III sprain, or a complete tear. The surgery for such an injury is very similar to the one needed for a ACL tear as well. The timeline for a return is also similar, ranging from three to nine months.

Finally, we are brought to the meniscus. This cartilage is positioned right in between the femur and tibia. The meniscus stabilizes, bears weight, and helps you turn your knee. It also helps protect the femur and tibia from contacting each other. The meniscus can be injured in a variety of ways, sometimes over years of wear and tear from cardio activities like running, and other times from traumatic collisions. In Flacco's case, it's almost certainly the latter. There is also a strong correlation between ACL and meniscus tears, with the two being almost mutually implicated.

The recovery time for a meniscus tear varies on the type of surgery used and the success of it. A timetable of about two months of rest in a knee brace and rehabilitation afterwards is about the standard prescription for this injury. But when you have two other torn ligaments like Flacco, this is essentially voided.

While the severity of Flacco's injuries are unknown to the public at this point, our very own Doctor Bobby Esbrandt believes that Flacco will be out between 9 and 12 months.

@BMoreBeatdown @sgellison It varies a bit from player to player. Likely in the 9-12 months range. — Bobby Esbrandt (@DrBobbyE) November 22, 2015

That timeline would put Flacco back on the field roughly between the start of the season and the mid-way point. Even with a quicker healing process, Flacco will still have the issue of mentally preparing for his knee to be there when he goes to plant and throw the football. While no one knows how Flacco will react to that side of things, it can cause some of the best players to take a little extra time before they are truly 100% again.

Adrian Peterson most notably returned from a torn ACL and MCL in less than ten months, and fellow quarterback Carson Palmer returned from his second ACL tear in nine months. A timetable like Palmer's would have Flacco back on the field for the middle of next year's preseason.

The Ravens will have some tough decisions to make, but it looks like they will have a physically healthy Flacco early in the 2016 season, allowing them to make moves like normal.