Saints puttin’ on blitz again vs. 49ers?

Get ready for three rematches in this weekend’s divisional round of the NFL playoffs, and a fourth game that appears to be a grudge match.

Houston is playing Baltimore again.

Denver is playing New England again.

The New York Giants are playing Green Bay again.

But the most interesting behind-the-scenes story — which is unconfirmed — involves the game that wasn’t played this regular season: New Orleans versus San Francisco.

Those teams squared off in the exhibition season — the debut of 49ers Coach Jim Harbaugh — and the Saints won, 24-3, in the Superdome.

Typically those preseason games are throwaways, but the Saints’ 24-3 home victory over San Francisco caused a stir because the Saints broke an unwritten preseason rule by dialing up all sorts of blitzes — 18 of them in the first half. Coordinator Gregg Williams’ defense registered six sacks and forced two fumbles.

“They brought pressure and we weren’t quite expecting all that for a first preseason game, especially from the first team,” 49ers quarterback Alex Smith, who was sacked twice, said at the time. “But we had to deal with it and we didn’t tonight.”

The 49ers did not grumble about the strategy.

Saints radio announcer Jim Henderson said in a Houston radio interview in August that New Orleans decided to blitz so much — a departure from preseason protocol — because Harbaugh did not contact Saints Coach Sean Payton during the week before the game to discuss how the teams would approach the exhibition in terms of pressuring the quarterback.

“From what I heard from some people, Sean Payton sort of expected Harbaugh to call him throughout the week and kind of figure out a gentlemen’s agreement as to how the game would be played,” Henderson told 1560 The Game, according to ProFootballTalk.com. “When that didn’t occur, Sean just said to Gregg, ‘Let the dogs out.’ And they did.”

The blitzing even caught some Saints players off guard.

“Trust me, it surprised me too, some of the calls he made early,” safety Roman Harper told the New Orleans Times-Picayune at the time. “I enjoyed it. It definitely speeds up the process of the quarterback.”

Asked about that Monday, however, Harbaugh said he: a) has no issue with the Saints or Payton, and b) is unaware of any customary calls to exchange strategy information for exhibition games.

“Don’t know anything about that,” Harbaugh told reporters. “You hate to deal with hypotheticals. What somebody might have said and what somebody didn’t say. It really becomes irrelevant. Certainly not aware of any gentleman’s agreement. Even asked my brother [Ravens Coach John Harbaugh], ‘Is there some kind of gentleman’s agreement that you call a coach before a preseason game?’ And he wasn’t aware of any.

“Even if there was, we wouldn’t do it anyway. We ask no quarter, we give no quarter, and that’s how we approach things.”

Either way, Saturday’s game will be a yardstick for the 49ers offensive line.

Only this time, they don’t plan to get thwacked across the backside with that yardstick.

sam.farmer@latimes.com

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