What does it mean to be a “battle-tested” team? Some squads deal with rampant injuries to key players, forcing backups to step up. This year, the Chargers and Giants come to mind, as both have thrived in spite of these challenges.

Sometimes, the battles take place off the field. Perhaps a four-game losing streak leads to a players-only meeting where teammates clear the air and reunite stronger than before.

The following analysis takes a more quantitative approach to the “battle-tested” question, assessing the frequency and outcomes of regular-season games decided by close margins. Among Super Bowl opponents, are more battle-tested teams more likely to win the big game?

The Super Bowl team with more regular-season games decided by three points or less has won eight times (42%) and lost eight times (42%). On three occasions, both opponents played the same number of close regular-season games (16%).

Super Bowl winners have averaged 3.3 games decided by three points or less during the regular season. Super Bowl runner-ups have averaged 3.4. Thus, the quantity of narrowly decided contests truly has been an inconsequential factor in who wins or loses the big game.

The Super Bowl team with more regular-season games decided by three points or less has covered the spread nine times (47%) and not covered seven times (37%). On three occasions, both opponents played the same number of close regular-season games (16%).

This marks a slight shift compared to the winner/runner-up question. Perhaps being “battle-tested” in this way has no material impact on prevailing. But there’s at least a slight advantage when covering the spread. This might suggest the betting markets are very slightly undervaluing these battle-tested teams.

The Super Bowl team with more regular-season games decided by eight points or less has won 11 times (58%) and lost eight times (42%).

Ah, now we’re getting somewhere. This is a more meaningful distinction, as it suggests a tangible advantage for teams that are, presumably, one score away from tying or winning a game when the final whistle sounds.

Notably, Super Bowl winners have averaged 7.5 games decided by eight points or less during the regular season. Super Bowl runner-ups have averaged 7.0. This marks a slightly wider gap than the three-point-or-less outcomes.

If we dig even deeper, there have been 11 Super Bowls in the last 19 years decided by eight points or less. In seven of those contests (64%), the team with the most regular-season eight-point games won.

The Super Bowl team with more regular-season games decided by eight points or less has covered the spread 12 times (63%) and not covered seven times (37%).

Back to market perception vs. reality. Notably, 61.3% of Super Bowl winners’ regular-season losses these last 19 years have been by eight points or less, compared to 57.6% of Super Bowl runner-ups’ losses.

So, on average, Super Bowl winners not only have competed in more “winnable” (eight-point margin) regular-season games than their counterparts, but they’ve also lost more of those games, resulting in win totals that are marginally more deflated than those of the Super Bowl runner-ups.

That’s not to say the runner-ups are less deserving of their relatively narrow wins. But it seems the betting markets don’t apply enough weight to some battle-tested teams.