Thinking large and outside the box, ESPN plans to attempt to acquire Al Michaels from NBC Sports for “Monday Night Football,” The Post has learned.

ESPN would like to team Michaels with Peyton Manning in its dream booth, according to sources. Manning is now ESPN’s top choice as an analyst after Tony Romo agreed to his 10-year, $180 million deal to remain with CBS last week.

ESPN has also shown interest in free-agent quarterback Philip Rivers, according to sources. Rivers, 38, has said he intends to continue playing. NFL free agency officially begins March 18, but agents can start talking to teams on March 16.

Joe Tessitore and Booger McFarland are ESPN’s current MNF team, but the network is strongly considering a change.

If ESPN had been able to sign Romo, it hoped to bring in Michaels as his partner, according to sources.

Besides adding the glamour of a Michaels-Romo combination to the telecast, Disney, which owns ESPN, would have head into its upcoming NFL rights negotiations with the biggest-name broadcast team in the business. Disney hopes to add more NFL and a Super Bowl for ABC/ESPN in the coming years.

The network believes a Michaels-Manning pairing would have the same sizzle as Michaels-Romo. Michaels, 75, is arguably the best NFL TV play-by-player ever, while Manning is one of the greatest quarterbacks in history.

Talks between NBC/Comcast and Disney/ESPN have yet to begin. Since Michaels has two years remaining on his contract, NBC could simply turn down ESPN’s request.

“Al is under contract for the foreseeable future,” NBC spokesman Greg Hughes said.

ESPN declined comment.

Another complicated aspect for ESPN is that Michaels and Manning may only arrive as a package.

For NBC/Comcast, at first glance, there would seem to be no reason to allow Michaels out of his contract. Why would it want to help Disney, especially with its sights on Super Bowls? Ultimately, it might decide it does not.

However, a deeper understanding of the dynamic inside of NBC’s “Sunday Night Football” booth raises the possibility it could let Michaels explore a return to Monday night to end his career by helping to restore prestige to a position he held for so long.

NBC has already hired Mike Tirico as Michaels’ replacement with the exact timing of the transition not entirely clear. Tirico is supposed to call more games soon, though. The end of Michaels’ contract coincides with the Super Bowl in Los Angeles in early 2022.

Tirico is expected to take over for Michaels full-time after the LA Super Bowl at the latest, but could be adding more games as early as this season.

In 2022, Michaels could retire, but he has shown no real inclination to do that and, in reality, the one-game-per-week NFL season only extends from August through early February. Ultimately, Michaels may not want to be dealt from NBC, as its Sunday games are the top-rated program on TV, a Super Bowl is on the horizon and he has been with this crew for the past 14 seasons.

Meanwhile, Manning is NFL TV’s white whale, having turned down every network since he has retired. It is believed if he ever enters the booth, it would have to be the exact right scenario.

If Michaels didn’t work out, ESPN could try to make Manning happy with others. Manning could be teamed with a co-analyst, though his brother Eli Manning is an unlikely option. Jeff Saturday, a current ESPN analyst and Manning’s former center with the Colts, is someone Manning may have in mind, according to sources.

If NBC gave Michaels the green light, he would likely receive a hefty raise in the process and could add Manning to his collection of analysts that includes Howard Cosell, John Madden and now Cris Collinsworth.

There is precedent for a trade. In 2006, Michaels was set to continue on MNF as it transferred from ABC to ESPN, having agreed to a new deal to remain on the broadcast.

After Michaels’ MNF partner, John Madden, left for NBC, Michaels asked out of his signed contract. ESPN obliged, but it received Oswald the Lucky Rabbit in return.

Oswald was the precursor to the creation of Mickey Mouse. The rights to Oswald, though, were owned by NBC’s parent company then, Universal. It had been important to the Disney family to regain Oswald.

Now, nearly a decade-and-a-half later, ESPN is thinking large. It had a 10-year, $140 million offer it was hoping to present to Romo. It never got the chance. It is still big-game hunting — and it may need more than a lucky rabbit to pull it off.