It’s no secret that Bryce Harper and Manny Machado are free agents after the 2018 season. But there is a growing sense of urgency if the Washington Nationals and Baltimore Orioles want any chance of extending their young superstars contracts before they hit free agency. It’s only a matter of time before Harper and Machado become the highest-paid players in baseball history.

The best guess is that they’re on the same timetable and that less than 20 months from today they will agree on their next deals -- most likely with new teams. There’s also the possibility that Machado ends up getting more than Harper, but there is no embellishing what they’ll be paid. Here is a quick look at what I’m expecting Harper and Machado to receive if and when they get to free agency:

RF Bryce Harper, Washington Nationals
Age: 24 | Free Agent: After 2018

Harper was the best player in baseball in 2015, leading the league in OPS, home runs and WAR, while winning the National League MVP award. And after a down year last season, he’s back to looking like the dominant player he was two years ago. To become the first $400 million player in baseball, he will have to perform this year and next as he did in 2015; but if he does, as I said two years ago, he’ll set that record. The Boras Corp. has a long history of breaking records, and it will make sure he gets the highest average annual value (AAV) deal ever given, a record presently held by Zack Greinke of the Diamondbacks at $34.4 million. Baseball revenues are at an all-time high and continuing to trend upward. History has taught us player salaries always follow accordingly.

Harper will hit free agency at just 26 years old, which will allow him to get an 11- or 12-year deal to bring his last year of his contract through his age-37 or age-38 season. The reason I think he’ll get as many as 12 years is that when Robinson Cano and Albert Pujols got their 10-year deals, it took them to age 40, while a 12-year deal for Harper gets him to only 38. It’s already too late for the Nationals to try to extend Harper. He’s getting to free agency with the only question left: Will the Nationals try to trade him this offseason, rather than letting him just walk the following year?

Early Prediction: 12 years for a $35 million AAV
Total Value: $420 million

3B Manny Machado, Baltimore Orioles
Age: 24 | Free Agent: After 2018

Machado is possibly the best defensive third baseman in American League history, making plays that even 16-time Gold Glove recipient Brooks Robinson admits he couldn’t have made during his years at the hot corner for the Orioles. Machado also is a 40-homer power bat who would be an elite shortstop if whoever signs him decides to move him to that position. There are many in the business who would prefer Machado over Harper. Frankly, either could end up being the highest paid player in history. Machado is a much better player than Giancarlo Stanton, so he’ll dwarf Stanton’s $325 million pact; and he’ll get more per season than Miguel Cabrera did when he signed his $31 million annual salary, because that’s now considered an “old” contract.

Machado would like to remain an Oriole and finish his career at Camden Yards, and it’s hard to believe Baltimore wouldn't step up and try signing him after giving Chris Davis and Mark Trumbo a combined $36 million per year. It makes way more sense for them to give that money to Machado, especially with the inexpensive young power bat of Trey Mancini on your roster. You can’t sign Davis and Trumbo and then tell Orioles fans you can’t afford Machado. A 12-year deal takes him only to age 38, which is why I think he’ll get that length in his monster contract, as well.

Early Prediction: 12 years, $33 million AAV
Total Value: $396 million

The next superstar duo on deck

Once you’ve got your breath back after the money involved in the projected deals for Harper and Machado, put on your seat belt, because there are more future record-breaking deals to come. Nolan Arenado of the Colorado Rockies and Mookie Betts of the Boston Red Sox are like Vin Diesel in “The Fate of the Furious,” quickly zooming past most and suddenly threatening both Harper and Machado on the record-breaking roadways, runways and iced rivers. Arenado is a free agent the year after Harper and Machado get to the market, and Betts will follow a year after Arenado. If the Rockies or Red Sox want any chance of getting either one signed to reasonable deals, they need to get them signed as soon as possible, before Harper and Machado strike deals that will dramatically change the market for the next generation.

3B Nolan Arenado, Colorado Rockies
Age: 26 | Free Agent: After 2019

Much like Machado in the AL, Arenado is possibly the best defensive third baseman in National League history. He has led the league in home runs, RBIs and total bases in both of the past two seasons, and he already has won four consecutive Gold Glove awards. An MVP trophy is likely in his near future. Coors Field will have to be factored into what he’s worth to other teams, but it will not be enough of a deterrent from his becoming one of the highest paid players in the game.

It will be much cheaper if the Rockies can sign him now before he gets to free agency, where his value will balloon like it will soon for Harper and Machado. It’s reasonable that Arenado gets a 10-year contract in terms of length, like Joey Votto got from the Reds, especially since it would take Arenado to age 35 and not age 40, like it did Votto. Arenado's AAV will have to be just north of what Yoenis Cespedes got ($27.5 million).

Price tag for extending him now: 10 years, $28 million AAV
Total Value: $280 million

RF Mookie Betts, Boston Red Sox
Age: 24 | Free Agent: After 2020

In my opinion, Betts is the second best position player in baseball right now, behind only Mike Trout of the Angels. Betts is the ultimate five-tool player, and there is nothing he can’t do on the baseball field. He’s an elite defender in right field. He can run, hit, hit for power, throw, bowl and even drive golf carts into ponds. He’s humble, a leader, a competitor and, like Trout, a GM’s dream player. If he were a free agent, he would be the guy breaking all previous contract records, not Harper or Machado.

Fortunately for the Red Sox, he’s not a free agent until after the 2020 season, which means they get to enjoy having him for at least the next four seasons. However, they would be foolish not to try to sign him as soon as possible -- like the Angels did with Trout, the Marlins did with Stanton or the Braves did with Freddie Freeman -- to save millions.

Remember, by signing him this far out, they’ll be able to get him for much less on the surface than both Harper and Machado, because the Red Sox will be paying for three “arbitration years” instead of just “free agent” years, like Harper and Machado are going to be signing for. Betts won’t want to get tied up until the age of 31, because he’ll want to set himself up for another big contract, so he’ll probably prefer to go shorter in term of length but be willing to give up two free-agent years for the guaranteed deal. So the reason his AAV is only $22 million is because 2017 to 2020 will cover one non-arbitration year and three arbitration years. I have his AAV for his free-agent years of this extension set at $35 million, the same as Harper and Machado above. With this deal, Betts goes back on the market at age 28 primed for a 10-year deal that by then could project for him as the first $500 million position player.

Price tag for extending him now: 7 years, $22 million AAV
Total Value: $154 million