Jon Lester had to know when the Red Sox made their first offer in spring training.

They didn’t want him.

That may be harsh. Let’s just say the Boston Red Sox, one of the biggest spenders in Major League Baseball, did not want to pay market value for an ace pitcher like Lester, who turns 31 in January.

Market value? The Tigers gave Justin Verlander $180 million over seven years, starting in 2013, when Verlander turned 30.

Zach Greinke, a pitcher often compared to Lester, received $147 million over six years, beginning with this season, when Greinke was 30.

And what did the Red Sox offer Lester last spring: $70 million for four years. Yes, I know you and I wouldn’t mind a little raise like that. But this is baseball money and Boston management was going cheap on Lester.

Thing is, Lester let on that he would take less than market value – but not that less.

Both sides took the high road in the spring. Boston management said it wanted Lester and would continue talking. Lester said he was sure things would work out.

But Lester had to know, after that first offer, he was gone.

If both sides used full transparency, then their remarks might have sounded more like this.

Red Sox: “We like Jon. We really do. But we don’t want to give any 30-year-old pitcher a long-term contract. Those things rarely work out. No hard feelings.”

Lester: “Hey, I completely understand. It’s a business. I’ll be moving on. Thanks for the memories.”

Here is one of the public relations problems that the Red Sox have. Everything Lester does, he does it the right way (save for a chicken and beer episode in 2011, but Lester was a follower then).

Lester works hard and produces. When he occasionally fails, he’s accountable. When he succeeds, he’s classy. The fans love him.

And now the Red Sox want to dump him.

Just look at the Red Sox starting rotation before spring training: six veteran pitchers.

Ryan Dempster retired before workouts began. Jake Peavy was traded last week, and Felix Doubront was traded on Wednesday. By the time you read this, John Lackey could be gone, too. Then there is Lester.

That leaves Clay Buchholz standing, and he is hardly standing with strength, enduring a 5-7 season with a 5.87 ERA.

The Red Sox certainly have a lot of young pitching talent, but there is a gamble. How far can youth take Boston, without the experience of an ace like Lester to lead them?

And yes, it is possible that Boston trades some of that youth for a quality, veteran arm – and who knows if Cole Hamels will ever leave the Phillies, with four years left on his contract.

But management’s gamble may eventually become a wise – if not unpopular – one. It is risky giving long-term contracts to pitchers 30 and over.

Just look at Verlander. After he signed his contract, he put up his highest ERA (3.46) in eight years. His numbers this year – 9-9, 4.79 – don’t match that of an ace. He might continue this decline, and he still has five years left on his big contract.

Boston is a big spender but it does not want to be viewed as an out-of-control spender. Red Sox management bristles at being compared with the Yankees, whose payroll ($208 million) is 25 percent larger than Boston’s ($154 million).

Of course, New York is paying $23 million to 34-year-old CC Sabathia, who is injured for the rest of the year.

The Red Sox fancy themselves as a rich man’s version of the Oakland A’s – Moneyball with much more money.

The Red Sox obviously did not want Lester, even at a small discount. They just couldn’t say so. They want younger pitchers.

They may have a point. If you look at the top 10 pitchers in ERA in the American League, Lester is the oldest (although Scott Kazmir is only 17 days younger).

So maybe Lester has peaked?

Fans don’t want Lester to go, but they are also dealing with an ownership that has delivered three World Series titles in 10 years.

So those fans are being asked to believe that their team will be better off in the long run without Lester, their beloved ace.