But Dave Cameron (the author of the piece) assigns a 7 percent discount rate to the contract. The present value of $15 million per year over 14 years at a 7 percent discount rate is about $131 million. He chose 7 percent as the discount rate because that is the expected long run return of investing in the stock market.
A contract is not, however, like a stock. It is a bond--contracts have seniority to equity, and guarantee a particular cash flow. I would guess the Nats (unlike the Expos) are something like a BBB company. The current bond yield on BBB issues is currently about 3.6 percent. Discounting the value of the Scherzer contract at 3.6 percent produces a present value of $163 million. Not that $131 million isn't nothing, but $163 million is a lot more.
[Update: Adam Levitin says that MLB teams are more like AAA (in bond rating, not playing quality, except, perhaps for the Diamondbacks last year), because all of baseball backs team contracts (when the Rangers went bankrupt, all players got paid). That would drive the discount rate to 2.8 percent, and raise the value of the contract to $172 million.]