The Phillies opened last season with a payroll just under $96 million. Their average opening day payroll from 2016-18 was $95 million.

That figure has risen significantly with the acquisitions of Jean Segura and Juan Nicasio and the signings of Andrew McCutchen and David Robertson.

Following the Robertson signing Thursday, the Phils' payroll is just over $142 million. This factors in projected 2019 salaries for their nine arbitration-eligible players, their pre-arbitration players and their players on the 40-man roster who will open the season in the minor leagues.

Player benefits, which also count toward the luxury tax, push that number to around $157 million. The luxury tax threshold is $206 million this upcoming season and it's calculated at the end of the season, not the beginning of it. Adding or subtracting money to the books throughout a season impacts that luxury tax figure.

The Phillies have never in their history exceeded the luxury tax threshold. A first-time offender is forced to pay a 20 percent tax on their overages. Exceed it two seasons in a row and the tax is 30 percent. Three or more consecutive seasons and it's 50 percent.

The luxury tax figure uses the annual average value of a player's contract. So, for example, Andrew McCutchen is making $10 million this season on a back-loaded deal, but his AAV is $16,666,666. That higher number is the one that counts toward the tax.

The Phillies can still fit another gigantic salary onto their books without having to worry too much about the luxury tax. If they're able to land Manny Machado or Bryce Harper for $35 million to $40 million per year, their payroll number would jump to the $195 million range.

In other words, there is still room to add a superstar and another useful player like a mid-rotation starting pitcher. Money could also be freed up if the Phillies move on from Maikel Franco, Cesar Hernandez or both. That duo is projected to make $14 million combined through arbitration this winter.

So again, including everything that counts toward the luxury tax, the Phillies are at around $157 million as of Jan. 4. It's the third-highest figure in the NL East, behind the Nationals ($192M) and Mets ($166M). The Braves are closer to $115 million.

Still a good amount of work for Matt Klentak and the Phillies' front office to do. They've improved the infield, outfield and bullpen this offseason, but those additions won't be as meaningful to many fans if the Phils fail to land Machado or Harper.

They also need more starting pitching, even if it's just a No. 4 starter type for depth purposes. The Phillies could talk themselves into meaningful improvement from the young guys (Nick Pivetta, Zach Eflin, Vince Velasquez) and a bounce-back season from Jake Arrieta, but that's an everything-breaks-right scenario.

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