Andrew Whitworth “wanted to be a Giant” in 2017

The Giants weren’t interested — a mistake they have paid for ever since

After two seasons of watching Ereck Flowers flounder at left tackle, the New York Giants had a potential solution to their offensive line needs staring them in the face — free-agent Andrew Whitworth — and turned down the opportunity.

Whitworth, the best lineman on the free agent market, “wanted to be a Giants.”

“I actually had reached out and wanted to be a Giant just because I knew Eli Manning really well,” Whitworth told The Post. “But they kinda said no because they thought they were gonna continue with Ereck Flowers at left tackle, and that obviously didn’t end up working the next year. Once we got into it and realized that wasn’t an option, the Jets showed some interest but it wasn’t really something that I was that interested in doing.”

The Giants instead doubled down on Flowers, their 2015 first-round pick. They ended up with a struggling Flowers at left tackle, and some combination of Justin Pugh, Bobby Hart and Chad Wheeler at right tackle.

Whitworth ended up earning the second All-Pro honor of his career and now, at age 40, is still playing at a high level and will be at left tackle for the Los Angeles Rams this Sunday in Super Bowl 56.

Not signing Whitworth was somewhat defensible on the grounds that offensive tackles don’t usually continue to play at a high level into their late 30s. The flip side of that, of course, is that the Giants spent the next three season trying to prove they could win with an aging Manning at quarterback — and Whitworth would obviously have improved their chances.

Rather than signing Whitworth, who got a three-year, $30 million deal with the Rams, the Giants spent that money on wide receiver Brandon Marshall, tight end Rhett Ellison and offensive lineman D.J. Fluker.

The following year, they signed Nate Solder — a far inferior player — to a four-year, $62 million contract. In 2020, still seeking the quality left tackle they could have had in 2017, they drafted Andrew Thomas No. 4 overall.

There are many examples of poor decisions made by the Giants over the past decade. This turned out to be one of the big ones.