ALAMEDA, Calif. -- When Jon Gruden returns to the Oakland Raiders as head coach next week, it will be a full nine seasons since he last roamed a sideline -- and that was with the Tampa Bay Buccaneers. The

In his work as a Monday Night Football analyst since 2009, Gruden has kept himself "insanely prepared" as a coach on the air, a source said, digesting hours of tape, dissecting clips and studying up for the NFL draft.

But how different will the NFL landscape be from when Gruden last coached? ESPN research found five coaches who returned to the NFL after at least a four-year break, during the Super Bowl era, and only one had more success after the break than he did before it, let alone a record better than .500. The longer the break, the more success. Indeed, absence makes the coaching heart grow fonder.

Let's take a look at the five and their résumés:

Dick Vermeil

First incarnation: Philadelphia Eagles (1976-1982)

Record: 54-47 (.535) | Playoff appearances: 4 (3-4)

Second incarnation: St. Louis Rams (1997-1999), Kansas City Chiefs (2001-05)

Record: 66-62 (.516) | Playoff appearances: 2 (3-1)

Don’t shed any tears for Vermeil, who, citing burnout, retired at the age of 46 after a Super Bowl appearance, where he lost to the Raiders, and returned 15 years later. Television duties kept Vermeil busy before he decided to jump back to the sideline at the age of 61. It was in his third season when Trent Green was lost in a preseason game that Kurt Warner took over and the Rams won Super Bowl XXXIV. Vermeil retired again -- for a year -- before going across the state to coach the Kansas City Chiefs for five seasons, and going to the playoffs twice. Of the five coaches listed, he is the only one to have a record better than .500, and the only one to win a Super Bowl after the break.

Joe Gibbs

First incarnation: Washington (1981-92)

Record: 124-60 (.674) | Playoff appearances: 8 (16-5)

Second incarnation: Washington (2004-07)

Record: 30-34 (.469) | Playoff appearances: 2 (1-2)

Gibbs made two Super Bowl appearances in his first three seasons, including a Lombardi Trophy in Year 2 and won a second title in Year 7 and a third in Year 11. But after 12 years in Washington, Gibbs left the NFL grind for a run in motorsports with the NASCAR team he had created in 1991, Joe Gibbs Racing. That team, which has had the likes of Dale Jarrett and Kyle Busch, has won four Cup Series championships since 2000. Gibbs also went into NHRA and motocross, while doing some NFL analyst pregame show work for NBC before the NFL beckoned. Gibbs returned as Washington's coach and president, and while he did have two playoff appearances, he could not replicate his previous success, and his winning percentage was 205 points lower.

Tom Flores

First incarnation: Oakland/Los Angeles Raiders (1979-87)

Record: 83-53 (.610) | Playoff appearances: 5 (8-3)

Second incarnation: Seattle Seahawks (1992-94)

Record: 14-34 (.292) | Playoff appearances: 0

The first minority coach to win a Super Bowl (he did it twice and has two other rings as a player and assistant) was burned out from the Raiders fading in 1986 with four straight losses and the 1987 strike, as well as having to incorporate Bo Jackson midseason. Flores hoped to take a year off, but Raiders owner Al Davis hired Mike Shanahan instead, and Flores, bitten by the coaching bug, went to Seattle in 1989 as the Seahawks general manager from 1989 to 1991. He returned to the sideline in 1992 and, having drafted quarterbacks Dan McGwire and Rick Mirer, lasted just three seasons as coach. His fall in Seattle -- with his 318-point drop-off in winning percentage -- may be a major reason why Flores, who now does color commentary on the Raiders' radio network, is not in the Pro Football Hall of Fame. Flores, George Seifert and Jimmy Johnson are the lone eligible coaches with multiple Super Bowl titles who currently don't have a bust in Canton, Ohio.

Art Shell

First incarnation: Los Angeles Raiders (1989-94)

Record: 54-38 (.587) | Playoff appearances: 3 (2-3)

Second incarnation: Oakland Raiders (2006)

Record: 2-14 (.125) | Playoff appearances: 0

Al Davis said he always regretted firing Shell, a Hall of Fame offensive lineman for the Raiders and the first African-American coach of the NFL's modern era. Shell, the 1990 NFL Coach of the Year, had only one losing season in six during his first go-round. Davis, though, may have regretted bringing Shell back 12 years later. Sure, Shell stayed in the game as an assistant in Kansas City and Atlanta before working for the league as a senior vice president in charge of football operations. But when Shell returned, the game had passed him by, and the players did not respond well to him or offensive coordinator Tom Walsh, who had been running a bed & breakfast in Idaho. The 2-14 finish was not only a 462-point fall in Shell's winning percentage, it was Oakland's worst since Davis came to the Raiders in 1963 and ushered in coach Lane Kiffin and QB JaMarcus Russell.

Mike Ditka

First incarnation: Chicago Bears (1982-92)

Record: 106-62 (.631) | Playoff appearances: 7 (6-6)

Second incarnation: New Orleans Saints (1997-99)

Record: 15-33 (.313) | Playoff appearances: 0

Along with Flores, Ditka is the only person to win a Super Bowl as a player, assistant coach and head coach, and Ditka's outsized personality and success in his Chicago run made him "Da Coach." His Bears teams won six division titles in seven years and dominated the Patriots in Super Bowl XX, 46-10, but he could never replicate his Super Bowl Shuffle Bears' success. Fired after the 1992 season, Ditka went into broadcasting before the Saints came calling. Ditka trading eight draft picks to Washington to move up and select Ricky Williams at No. 5 in 1999 all but sealed his fate, as he went 3-13 that season. But not before the memorable wedding photo on the cover of ESPN the Magazine that had Williams in a wedding dress and Ditka as the groom with the headline, "For Better or Worse." It was worse, like his 318-point fall in winning percentage.