One of the patients in critical condition had a blood clot on the brain removed in emergency surgery, doctors said at an afternoon press conference at Grady Memorial Hospital.
"The next couple of days is going to tell here, " said Dr. Jeffrey Salomone at Grady, when asked if those in critical condition would survive.
Doctors said the most critically injured tended to be near the front of the bus.
I-75, just north of downtown was closed for five hours during the morning commute but since reopened.
Federal, state and county officials are investigating why the tour bus carrying the Ohio team to a spring break tournament in Florida, crashed at full speed this morning.
Atlanta police said the driver of the southbound bus apparently exited the interstate at "highway speed" at Northside Drive but made no attempt to stop at the intersection. The bus was travelling in the HOV lane, the far left lane of the busy roadway.
There were no skid marks on the pavement, indicating the driver either did not attempt to stop or there was a mechanical failure, police said.
Survivors have spoken with investigators and told police the bus was travelling at highway speed as it attempted to negotiate the turn onto Northside Drive, crossed several lanes of traffic and crashed through a retaining wall and fence before falling onto the southbound lanes of the interstate.
Atlanta police Maj. Calvin Moss said the driver was "fresh, " having taken the wheel about 4:30 a.m., an hour before the crash. There was no indication drugs or alcohol were a cause of the crash, police said.
An electronic device on the bus will be used to determine more about the accident, said an official with the National Transportation Safety Board, which is investigating the wreck along with local authorities.
Ramthun, who is 19, said Curt Schroeder, a sophomore catcher on the "tightly knit" team, tapped him on the head "telling me we needed to get out because there was gas all over the place, " the bruised Ramthun told a group of reporters outside of Grady Hospital.
"I heard some guys crying, I'm stuck, I'm stuck. I walked by Coach Grandey, who is now in stable condition, but at that time he was so bad off. And I tried to help him up and that's when I realized my shoulder was hurt.
"It was just chaos in my mind."
Bluffton Coach James Grandey, 29, was among the three seriously injured. He is listed in serious condition at Piedmont Hospital but is expected to improve.
Ramthun looked around for his brother, Mike, a sophomore, but could not find him. His brother was trapped under the bus and has an injured hip.
"He might not recover, " Ramthun said, saying he was already feeling guilty because he suffered only slight injuries to his collarbone and face. "And I don't know how to come up to some of these guys and say, I'm sorry, while I'm standing.
Listed on the team's roster is a metro area athlete, pitcher Tim Kay, from Alpharetta. His father, Ed Kay, said Timothy was "in good shape" and only suffered cuts and scratches.
The elder Kay served as kind of a surrogate father for several of the team members who milled around Grady hospital in shock.
"The boys are doing pretty well, " said Ed Kay. "Some of them are walking around. They're talking to each other. They're obviously concerned about their teammates and their coaches and the other people that were on the bus. Most of them are in reasonably good spirits, about as good as can be expected."
Allen Slabaugh, a sophomore pitcher on the team from Dalton, Ohio, was thrown from the bus with three other passengers and luggage before the vehicle plunged from the bridge, said Chester Slabaugh, the student's father.
The student suffered "some stitches, " his father said. He did not think the others who were ejected were hurt badly.
"He was sleeping and then got ejected before it went over the bridge, " the senior Slabaugh said Friday morning as he prepared to go to the airport. "He did not go over, by the grace of God."
Atlanta fire officials said 55 firefighters responded to the scene, as well as emergency medical workers from area hospitals. Crews had to use the jaws of life to extricate some passengers, as well as shore up the vehicle to stabilize it for rescue operations.
MARTA sent a bus to help carry the least injured passengers to hospitals.
The 13 baseball players who boarded his MARTA bus were walking and not visibly injured, sais Darryl Murphy, a MARTA bus supervisor. The young men were subdued and didn't say much, he said.
As the bus lay on its side perpendicular to the interstate lanes, passengers began crawling out, helped by motorists who had stopped beyond the wreck. Luggage and personal belongings were scattered over the highway.
At about 10 a.m., a tow truck was seen pulling the bus away from the accident scene.
On Northside Drive, above the wreck, luggage and baseball equipment was scattered on the road, apparently dislodged from the bus when it hit the bridge's 2-foot-high retaining wall and crashed through a 10-foot-high fence atop the wall.
The plunging bus clipped two trucks that were southbound on 75. A Chevrolet sport utility vehicle and a pickup truck were hit but neither driver was injured.
Danny Lloyd of Frostburg, Md., who was driving the pickup truck thought it a "big slab of concrete" falling from the bridge on top of him.
"I just closed my eyes and stepped on the gas, " said Lloyd, who was traveling from Cincinnati to Florida.
Lloyd slid by the bus, getting hit on the roof. His front bumper was torn off.
Bluffton University is affiliated with the Mennonite Church USA and according to the school's Web site, "students will scatter East, West and yes, South, to serve, minister, perform and play ball during spring break, March 3-11."
Some students were headed for Louisiana to work with Mennonite disaster services to aid Katrina victims, a student drama ministry team was headed to churches in Indiana, Minnesota and Illinois. Another group, the Camerata Singers were touring in the East. Their theme was "Through Faith and Prayer."
The baseball team was headed to play Eastern Mennonite in Sarasota, Fla., on Saturday, and then onto the Gene Cusic Classic in Ft. Myers, Fla. to play in annual tournament, where more than 300 teams, many or most from "cold weather climate" states come to play a week's worth of games during spring break.
This is a sad tragedy for the students, families, friends and Bluffton University campus community. We are asking for prayers of support during this time, " said Bluffton University President James M. Harder."
The bus company, Executive Coach Luxury Travel from Ottawa, Ohio, did not immediately return a phone call. The company carried a statement on its Web site, titled "We Grieve."
"We at Executive Coach Luxury Travel Inc. are deeply saddened by this travesty. We are continuing to cooperate with the officials investigating the accident in Atlanta, Ga. Our thoughts and prayers are with all of the victims and their families."
Bluffton is one of two Heartland Collegiate Athletic Conference teams that for several years have hired the bus company for long distance travel "without difficulty or problem, " said conference commissioner Tom Bohlsen.
Hiring a bus allows a college team to avoid a coach or staff member driving the team in a school-insured van, Bohlsen said.