When you play football at Swampscott High, every game is a big game. But in terms of past and present context, Thursday’s game against Marblehead at Blocksidge Field may be among the biggest in the history of the program.Not only is this year’s Thanksgiving Day showdown the 100th game between the two bitter rivals, there is the bonus of the Northeastern Conference Small championship and a berth in the Div. 3 playoffs at stake for the winner.Just as the Magicians would like to deny Swampscott a chance to repeat as Super Bowl champions, the Big Blue would like to keep the Magicians from completing a historical run to their first-ever post-season berth.”It’s a playoff game,” Swampscott coach Steve Demboswki said. “If we win, we get to keep playing football. If they win, our season is over.”At first glance, it would appear the Big Blue (8-2; 3-1 NEC Small) would have the advantage over the Magicians (6-4; 3-1). The defending champs are the only team in the conference to knock off Gloucester, and would be undefeated absent two losses in the last minute of games against Winchester and Beverly, by a total of five points.The Swampscott players who were on the roster last year have also seen enough pomp and circumstance to not get fazed by the ceremonies that are planned for the 100th game. This is a poised, confident group that knows how to win and will be playing at home.Also, the Big Blue has an advantage in that Marblehead quarterback Hayes Richardson and his backup, Ian McKinley, will not be playing on Thursday due to suspensions. The Magicians, who are coming off a 41-13 defeat to a Saugus team Swampscott beat by three touchdown, will likely start a sophomore at quarterback.Dembowski is cautioning his team and everyone else not to take Marblehead lightly, however.”They lost one starter; one,” Demboswki said. “They’re a good team. They’re in the position they’re in because they’ve played well all season long. They’re not a fluke and it would be a mistake to think we can play anything but our best game and still beat them.”The Big Blue will also be without their leading receiver, Trevor Wheeler, who is out for the season with an injury. Backs Kyle Shonio (who Dembowski lists as questionable) and Ilya Levin (doubtful) are also hurt.”You don’t replace a player like Trevor Wheeler,” Dembowski said. “He’s one of the best receivers on the North Shore, if not in the entire state.”Swampscott still has the leader of its spread offense, Chris Cameron, who is second in Div. 3 with 20 touchdown passes and has scored 12 more. Cameron will almost certainly accumulate some post-season honors, including the conference’s player of the year.While Swampscott’s offense has put up 314 points, its defense has been much tougher lately, holding four of its last five opponents to less than 21 points, and yielding just 19 points in its last two games.After the season-opening 30-29 loss to Winchester that was decided by a field goal with 17 seconds left, the Big Blue started rolling when Cameron scored a pair of second half rushing TDs to beat Revere, 28-22.That victory kicked off a 7-game win streak which had some dramatic moments. The following week against Lynn English, Cameron threw for 248 yards and three touchdowns as Swampscott held off a late English rally to win, 34-32.Cameron tossed five more TDs in a 47-26 win over Salem the following week, setting up a showdown at Gloucester on Oct. 10. The Fishermen led, 14-7, at the end of the third quarter, but Wheeler caught a paid of scoring passes and Cameron ran for a third to seal a 28-20 win.The Big Blue scored 42 points in the first half of an annihilation of Bishop Fenwick, but again had to rally from behind to catch Winthrop for a 34-32 victory, with Cameron scoring the winning touchdown with 30 seconds left.Levin scored a pair of rushing touchdowns while Shawn Hubauer added a third in the win over Saugus, but Beverly upset the Big Blue, 20-16, the following week in another game that was decided in t