They say the best negotiations are done when both sides walk away a little unhappy.

But what about when both sides leave equally pleased?

That had to be the case when the St. Louis Cardinals and right fielder Stephen Piscotty announced a six-year contract extension Monday that guarantees Piscotty $33.5 million over the course of the deal, and bumps his current salary of $1.3 million this season to $7.3 million by 2019.

The 26-year-old Stanford graduate could have bet on himself and taken the team to salary arbitration at the end of next season.

There, a committee would hear arguments from Piscotty and the team before deciding on a one-year salary.

A productive pair of seasons this year and next would have likely netted Piscotty more than the $7.3 million he is now owed in 2019.

But four years at Stanford probably taught the 6-foot-3, 210-pound righty that the only thing guaranteed in Major League Baseball is the contracts, and signing a long-term deal negated any risk of injury or poor performance the next two seasons.

Piscotty hit .273 last season, his first full year in the majors.

He projects as a future all-star with power who also can hit for average, which probably made the Cardinals’ decision to lock him up now an easy one.

The deal continues the club’s insistence on signing young talent to long-term, team-friendly contracts before the player is eligible for free-agency.

Players like Matt Carpenter, Kolten Wong and Yadier Molina have signed long-term, cheaper deals to stay in St. Louis in the last decade.

In Carpenter and Molina’s case, both sides benefited.

And while Wong’s five-year, $25 million contract he signed last season has yet to pay off for the club, these types of deals have helped the franchise stay (relatively) on top without chasing success in free-agency.

Because the problem with chasing high-priced free agents isn’t just the price tag.

It’s the number of teams in the hunt.

If one foolish owner over-spends on a player, a competitive offer doesn’t mean a thing.

In late 2015, the Cardinals reportedly offered starting pitcher David Price a seven-year, $187 million contract.

It would have been the largest contract in franchise     history.

Price took $30 million more from the Red Sox.

Four years earlier, Albert Pujols scoffed at St. Louis’ 10-year, $210 million contract, instead signing with the Los Angeles Angels for $254 million.

You can see how chasing the high-priced players could wear on a general manager.

Locking up young players with potential is cheaper and easier, with less risk involved.

And while Piscotty looks like a player who could command a contract twice that size down the road in free-agency, I’m not going to tell a guy with a degree in atmosphere and energy engineering from Stanford he made a bad financial decision.

Would you?