There probably aren't another two NFL coaching staffs who know each other as well as the 49ers and Green Bay Packers.
And that is how it sets up Sunday for the NFC Championship Game at Levi’s Stadium.
The 49ers and Packers met this season in Week 12, and the Niners had few problems in a 37-8 victory.
But that makes little difference now. The Super Bowl is on the line, as the Packers advanced to the NFC title game with a 28-23 victory over the Seattle Seahawks on Sunday at Lambeau Field.
The connections run deep with the two coaching staffs.
Coach Kyle Shanahan, who runs his 49ers offense, will be matched against Packers defensive coordinator Mike Pettine. In 2014, Pettine, as head coach of the Cleveland Browns, hired Shanahan as his offensive coordinator.
Shanahan was so miserable after one season, he got out of his contract in order to go to work for Dan Quinn with the Atlanta Falcons.
Meanwhile, Packers head coach Matt LaFleur, who runs his team’s offense, will be playing chess against 49ers defensive coordinator Robert Saleh. LaFleur and Saleh have been best of friends since their days together as graduate assistants on Central Michigan’s coaching staff in 2004.
Saleh took an entry-level job with the Houston Texans in 2005. Three years later, LaFleur was hired for a quality control position with the Texans after Saleh recommended him for the job.
The NFC Championship Game should feature plenty of good matchups on the field, too. Here are some of the most important head-to-head battles that could decide which team represents the NFC in Super Bowl 54:
QB Jimmy Garoppolo vs. LB Blake Martinez
Jimmy Garoppolo must beware of the linebacker dropping into coverage.
Garoppolo has given linebackers chances to make plays because he sometimes locks onto his receiver and gives the underneath defender an opportunity to read his eyes and react to make a play.
That is exactly what happened Saturday when Minnesota Vikings linebacker Eric Kendricks picked off a Garoppolo pass right before halftime.
But in this game, Garoppolo certainly will look to exploit this matchup. He has a chance to feast. But he also has to use his eyes to move the linebackers and safeties.
One of the weaknesses of the Packers' defense is their linebackers’ ability to cover. Blake Martinez in coverage gave up 58 completions on 69 passes thrown his way for 500 yards, according to Pro Football Focus.
FS Jimmie Ward vs. QB Aaron Rodgers
Nobody on the 49ers has been through as much as Jimmie Ward to get to this point in his career for the first time. Ward seemingly has found a home at free safety after bouncing around in the secondary through his first five injury-plagued NFL seasons.
Rodgers will take deep shots – especially after using the hard count to try to draw the 49ers’ pass-rushers offside. And when he does, Ward has to live up to his job description as “the eraser.”
Ward had a good game in November against Rodgers, who completed just 20 of 33 attempts for 104 yards with one touchdown and no interceptions. Ward had two pass breakups down the field, one against wide receiver Davante Adams and one against tight end Jimmy Graham.
Rodgers’ longest pass play that day went for just 15 yards. The key for the Packers will be to hit big plays down the field. Ward is the key to preventing those big plays.
CB Emmanuel Moseley vs. WR Davante Adams
Veteran cornerback Richard Sherman has been a rock. But the 49ers have experienced plenty of uncertainty on the other side.
Emmanuel Moseley exudes confidence without a trace of bravado or conceit. He will be ready to make the start at right cornerback Sunday, and it seems logical the 49ers would place their trust in him.
For the second game in a row, Moseley replaced struggling Ahkello Witherspoon. Moseley allowed just three receptions on six passes thrown his way for 24 yards against the Vikings.
The Packers’ top receiver is Davante Adams, who does a lot of his work lined up on the left side. Adams had eight catches for 160 yards and two touchdowns in the Packers’ win over the Seahawks.
When the teams met earlier this season, Moseley started. The Packers targeted Adams only two times against Moseley. Adams caught one pass for 14 yards. Overall, Adams had seven receptiions but for just 43 yards.
With as well as Sherman is playing, this figures to be the matchup the Packers will look to exploit.
LT Joe Staley vs. DE Za’Darius Smith
Joe Staley did not play when the 49ers met the Packers earlier this season. Rookie Justin Skule lined up at left tackle while Staley missed action this season with a broken lower leg, then a fractured finger. Smith had 1.5 sacks against Skule.
Smith is playing with a purpose. He registered 13.5 sacks and did not make the NFC Pro Bowl team. After picking up a sack Sunday against Russell Wilson, Smith revealed the bottom of his undershirt, that had the word, “SNUBBED,” stamped at the bottom. He will be out to make a point against Staley, a six-time Pro Bowl performer.
Staley is playing at a very high level at the exact right time for the 49ers. He is coming off two very strong games, including Saturday in the divisional round of the NFC playoffs against the Vikings. Staley did not allow a quarterback pressure against Everson Griffen.
Of course, every aspect of the 49ers’ pass protection benefited from the team’s ability to run the ball consistently and effectively against the Vikings. The 49ers will want to follow the same formula Sunday at Levi’s Stadium.
LB Fred Warner vs. RB Aaron Jones
The 49ers did not allow Aaron Jones to do much when the teams met earlier this season. The Packers must find a way to get him going or it could be a long day for Rodgers.
Linebacker Fred Warner registered 11 tackles in the Week 12 win, four of which came against Jones. Jones managed only 38 yards on 13 rushing attempts (2.9 average). He did not catch a pass.
Jones rushed for 1,084 yards and 16 touchdowns in the regular season. He had 63 yards rushing with two touchdowns Sunday against the Seahawks.
DE Nick Bosa vs. LT David Bakhtiari
Packers left tackle David Bakhtiari earned Pro Bowl recognition after a season in which he surrendered just two sacks the entire season. But Nick Bosa had an impactful game when they met earlier this season. And, before that, his brother, Joey Bosa of the Los Angeles Chargers, had a good game against Bakhtiari.
Nick Bosa had six quarterback pressures in the meeting against the Packers earlier this season.
The entire defensive line appeared to benefit from the return of Dee Ford, who played just four snaps in the final six weeks of the regular season due to a hamstring injury. Ford made it back for the divisional round of the playoffs, and the 49ers' pass rush was outstanding. The 49ers sacked Kirk Cousins six times.
On Sunday against the Vikings, Bosa had two sacks, one quarterback hit and four hurries. He had three run stops on just seven snaps against the run, according to Pro Football Focus.