If the Philadelphia Phillies want Bryce Harper to stop hitting walk-off home runs against them and start hitting them for them, it's not going to be cheap.
An anonymous general manager that spoke to Jon Heyman of FanRag Sports suggested that Harper, who can become a free-agent after 2018, may push a half billion dollar contract:
One rival GM pegged Bryce Harper’s value on a long-term deal at “closer to $500 million than $400 million,” a seemingly stark admission for a management person, even if it isn’t a Nationals person.
That executive, claiming Harper is “twice the player that Giancarlo Stanton is,” suggested $400 million is the absolute baseline for a Harper deal.
Prior to the season, an anonymous scout predicted that Manny Machado, not Harper, would receive the league's first $400 million plus contract. While Machado, who also can become a free-agent after 2018, may get that amount in free-agency, it seems laughable now to think that Harper won't get at least $400 million.
After an injury-riddled 2016 season, Harper has played much more like the 2015 version of himself that won the National League MVP. Still just 24, Harper is slashing .376/.491/.744 with 14 home runs and 36 RBIs.
Certainly, allocating $40-$50 million to one player would be a risky investment.
First, it would take up a giant chunk of the available funds of whatever team signs him. In signing a player to a deal like this, the signing team would probably have to make a commitment to go over the luxury tax threshold, which certainly would take an ownership group committed to winning.
Secondly, any deal of this magnitude takes on the risk that a player will underperform. That said, if there's a such think as a safe deal in the neighborhood of 10-years/$475 million, this would be it. Harper will only be 26 when he becomes a free-agent, so you would presumably be getting him for the best years of his career. If he plays the entire length of the deal, he'll only be 35 at the start of the 10th season of the deal. In all likelihood, Harper will opt-out of the deal around six years in, to attempt to get another 10-year deal to complete his career, just like Alex Rodriguez did. So in signing Harper after 2018, the Phillies would likely only be locked into paying a generational talent for his prime.
Given that the post-2018 season free-agent class is expected to be the deepest in the history of the sport, there's an argument to be made for allocating the money that would be used to sign Harper to multiple players. But if you are against signing Harper, it's hard to be in favor of signing Machado, because he will probably get a similar amount of money. And to obtain Mike Trout, the Phillies would likely have to trade a bulk of their farm system and give him an extension larger than either Harper or Machado's.