FOXBOROUGH, Mass. — The essence of the New England Patriots’ reign as this century’s most successful N.F.L. team has been their peculiar capacity to feel smug and belittled at the same time.

It is a paradox the Patriots have put to good use at pivotal times on the way to five Super Bowl victories, winning some games because of unbridled confidence and others because they believed they were being unfairly disparaged.

Sunday’s 41-28 thrashing of the Los Angeles Chargers in an A.F.C. divisional round playoff game — the Patriots led by 28 points at halftime — was conspicuously in the latter category. After an uneven season in which New England stumbled through the final quarter of its schedule and many in the N.F.L. community prepared an obituary for this dynasty, the Patriots had built up a fair amount of righteous indignation.

The result Sunday was a furious ambushing of the visiting Chargers, a talented team largely relegated to being bystanders as New England scored 28 unanswered points before halftime to put the game virtually out of reach. Proof of the Patriots’ mind-set for the afternoon came minutes after the final whistle when quarterback Tom Brady stared into a television camera during an on-field interview.