CLEARWATER , Florida -LRB- CNN -RRB- -- Two NFL players are among four boaters missing since Saturday night off Florida 's Gulf Coast , officials told CNN . Corey Smith , left , and Marquis Cooper are missing after a boating trip off the Florida coast , officials said . Oakland Raiders linebacker Marquis Cooper and NFL free agent Corey Smith , who played for the Detroit Lions for the past three seasons , have not returned from a Saturday fishing trip in water off Clearwater , Florida , family members and colleagues said Sunday . `` It feels like my greatest fear coming true -- it does n't feel real , '' Cooper 's wife , Rebekah , told CNN affiliate WTSP in Tampa on Sunday afternoon . `` I 'm just waiting for a phone call . '' The Coast Guard began searching around 2 a.m. Sunday after it learned that four men -- Cooper , Smith , and former University of South Florida football players William Bleakley and Nick Schuyler -- had not returned from their fishing trip Saturday evening as expected . Rough weather has hampered the effort , but `` it 's still a very active search , '' Coast Guard Capt. Tim Close told reporters Sunday afternoon . Poor visibility from heavy waves forced the search-and-rescue effort to be conducted primarily by air , though authorities deployed patrol boats as well , Close said . Watch relatives , friends express concern for missing boaters Â '' Searchers have focused on 750 square miles of open water in the Gulf of Mexico , about 50 miles west of Clearwater Pass . From there , the men had left the Seminole Boat Ramp in a 21-foot single-engine boat about 6:30 a.m. Saturday , the Coast Guard said . Rebekah Cooper said she became worried Saturday night when she did n't hear from her husband . She called her one of her husband 's fishing buddies , Brian Miller , who contacted the Coast Guard with the coordinates of where the men planned to fish . `` Usually I 'm on the boat . It 's a little difficult wondering if something would have been different if I had been there , '' Miller said . `` Or who knows ? They may be just sitting out there with a broken motor -- and that 's what we 're hoping for . `` He said it was clear something was wrong when Cooper did n't call Saturday night . `` He should 've been within range to use his cell phone , and he knows enough to shut it off when he goes out so the batteries are still there , '' he said . Close said weather conditions were relatively good Saturday , `` but the weather picked up overnight . '' `` It 's a small vessel for the conditions that are out there right now , '' Close said Sunday afternoon . Rebekah Cooper said her husband was aware of Sunday 's weather forecast and for that reason picked Saturday for the trip . `` Fishing is his first love , it always has been , '' she said , adding , `` I have a lot of faith in him out there . '' Cooper 's father said he learned of the situation Sunday morning from his daughter-in-law . His son `` routinely stays out on the water 12-14 hours , '' Bruce Cooper , a sports anchor for CNN affiliate KPNX in Phoenix , Arizona , said in a statement . Close said authorities had not received a distress signal from the boaters . Close said Cooper owns the boat . Bruce Cooper called his son an `` avid fisherman . '' `` He goes deep sea fishing any opportunity he gets , '' Cooper said in the statement . `` Two years ago I went deep sea fishing with him . I swore I would never do so again ; I did n't like the fact that I could n't see land . Needless to say I am very concerned . I am praying and hoping for the best . '' The boat , a center-console vessel manufactured by Everglades Boats , is billed as `` unsinkable , '' Close said . The Detroit Lions released a statement acknowledging that Smith was among the missing men , adding , `` Our thoughts and prayers are with all the passengers , their families and all those involved in the search efforts . '' Smith and Cooper were teammates with the Tampa Bay Buccaneers for part of the 2004 season , when Cooper was a rookie , according to the NFL 's Web site . Smith , who entered the league with Tampa Bay in 2002 , went on to play for the Washington Redskins before moving to the Lions for the 2006 season . Cooper has played for six teams in his five-season career . Cooper played college football at the University of Washington . Smith played at North Carolina State . Schuyler 's father , Stu , told reporters that the four men knew each other from working out at a gym , and that his son had accompanied Cooper and Smith on a fishing trip last week that lasted 15 hours . Bleakley lettered from 2004 to 2006 as a tight end for USF , according to a spokesman for the university 's athletics department . Schuyler was a walk-on defensive end for USF in 2006 , but he never played in a game , the spokesman said . `` Our thoughts and prayers are with the family and friends of Will and Nick , as well as the Florida Coast Guard as they continue their search , '' USF Athletic Director Doug Woolard said in a statement Sunday . The Coast Guard asked anyone with information on the boaters to contact its St. Petersburg , Florida , office at 727-824-7506 . CNN Radio 's Ninette Sosa contributed to this report .