After having to miss the workout portion of the combine in February, Southward didn't expect to hear his name called until the third and final day of the draft.
Instead, the Atlanta Falcons chose him as the fourth pick of the third round - 68th overall - and Southward says they won't regret the decision.
It was such a surprise that Southward had to call an impromptu draft party at his parents' home in Toledo, Ohio. Southward believed he would get picked the next day.
"I had no idea the Falcons had interest in me," Southward said at the start of Atlanta's rookie minicamp. "I never had a team visit or any calls or anything like that. Just so happened that 15 minutes before the 68th pick, they called me. I'm excited to be here."
Southward wasn't allowed to participate on the field at the combine because one of the league's 32 teams questioned the health of his spine.
After a doctor cleared him, Southward excelled at Wisconsin's pro day just 10 days after the combine, and the Falcons scouts were impressed.
He was the second of seven draft picks the Falcons made last weekend on defensive players.
Southward, a fifth-year senior, also was overcoming a wrist fracture, but Atlanta general manager Thomas Dimitroff was sold that health was not an issue.
Southward likewise impressed the Falcons by never missing a game in his career with the Badgers
"This is a guy who is big and fast, really good natural agility and movement for a bigger safety," Dimitroff said. "He has had one of the best three cone times, which is usually an indicator of body control and movement. He has cover skills and very good range for us, so we think he has some real upside to continue to bolster this secondary group."
Coming off a 4-12 season, the Falcons are rebuilding their defense. During free agency in March, they signed veterans Tyson Jackson and Paul Soliai on the line and later added Dwight Lowery, Josh Wilson and Javier Arenas in the secondary.
Defensive coordinator Mike Nolan will deploy a hybrid scheme using 4-3 and 3-4 fronts as the Falcons seek to improve a unit that ranked last in third-down efficiency, second-worst against the run and third-fewest in sacks.
Atlanta took Minnesota defensive end Ra'Shede Hageman in the second round and linebackers Prince Shembo of Notre Dame and Marquis Spruill of Syracuse each in the fifth.
In the seventh, the Falcons chose Connecticut linebacker Yawin Smallwood and South Dakota linebacker Tyler Starr.
Three of the four starters in the secondary - strong safety William Moore, left cornerback Robert Alford and right cornerback Desmond Trufant - are locked in at the top of the depth chart.
Southward will compete with Lowery and Kemal Ishmael at free safety. Thomas DeCoud was the starter for the past five years, but he signed with Carolina after getting cut.
For a 22-year-old whose football career didn't begin until his senior year at St. Thomas Aquinas High School in Fort Lauderdale, Florida. Southward believes he has picked up the game quickly after spending his athletic career in basketball and track.
He set a Wisconsin record by appearing in 54 games and was a starter the last two years. He ended 2013 with 40 tackles and had six pass breakups to rank second on the squad.
Falcons secondary coach Tim Lewis has told Southward the team is looking for a leader at free safety who doesn't make mistakes.
"Half the time it's not the guys making plays but it's the guys not making any mistakes," Southward said. "Not making mistakes first, but being able to go out there and cover some ground and be physical is critical, too. That's what you want out of any safety, and that's what I plan to do."
NOTES: After Saturday's practice, Falcons coach Mike Smith expressed sympathy for WR Roddy White, whose brother, Tyrone Moore, Jr., died of a gunshot wound outside a South Carolina nightclub early Saturday, according to a report in the Charleston Post and Courier. "We offer as a Falcons family our condolences to Roddy and his family in this very difficult time," Smith said. Moore, 21, formerly lived with White in the Atlanta area.