Cy Young winner Felix Hernandez will make nearly $23 million this season. The Mariners are worth $710 million. / Getty Images

Boosted by the revenue potential in the April 2013 purchase of a controlling interest in the Root Sports regional television network, the Seattle Mariners are worth $710 million, according to Forbes magazine’s March valuations of Major League Baseball teams.

It’s approximately a 10 percent increase from last year when the club was valued at $644 million but it doesn’t alter their financial standing compared to the rest of the league.

In each of the last two years, the Mariners were the 12th-most valuable franchise, according to Forbes. The magazine’s latest estimates reports the club grossed $210 million in revenue and earned a $5.3 million operating income in 2013.

The average value of a franchise is $811 million, a nine percent gain from last year. Unsurprisingly, the New York Yankees, for the 17th consecutive year, topped the list at $2.5 billion while the Tampa Bay Rays were last at $485 million.

The Oakland Athletics, who won the American League West and finished 25 games in front of the Mariners in 2013, ranked 28th ($495 million).

Here’s how Forbes estimates the worth of an MLB team:

Values are enterprise values (debt plus equity) and include completed television deals that begin in the future, but exclude the equity interests in other assets the team may own, such as regional sports networks or concession businesses. Revenues and operating income figures include all revenue and expenses for each team and its stadium where applicable.

In the magazine’s brief summary of the Mariners, it points to last year’s deal with Root Sports. The Mariners own 71 percent of the network while DirecTV owns 29 percent.

Beginning with the 2014 season the rights fee for Mariners will average $103 million over 18 years with the total value of the deal, including the team’s equity stake, worth an estimated $2.5 billion. No wonder the Mariners made the biggest free agent splash of the off-season by inking second baseman Robinson Cano to a 10-year, $240 million deal.

Here’s the rankings of values, courtesy of CBS Sports:

1. New York Yankees – $2.5 billion
2. Los Angeles Dodgers – $2 billion
3. Boston Red Sox – $1.5 billion
4. Chicago Cubs – $1.2 billion
5. San Francisco Giants – $1 billion
6. Philadelphia Phillies – $975 million
7. Texas Rangers – $825 million
8. St. Louis Cardinals – $820 million
9. New York Mets – $800 million
10. Los Angeles Angels – $775 million
11. Atlanta Braves – $730 million
12. Seattle Mariners – $710 million
13. Washington Nationals – $700 million
14. Chicago White Sox – $695 million
15. Detroit Tigers – $680 million
16. Baltimore Orioles – $620 million
17. San Diego Padres – $615 million
18. Toronto Blue Jays – $610 million
19. Minnesota Twins – $605 million
20. Cincinnati Reds – $600 million
21. Arizona Diamondbacks – $585 million
22. Colorado Rockies – $575 million
23. Pittsburgh Pirates – $572 million
24. Cleveland Indians – $570 million
25. Milwaukee Brewers – $565 million
26. Houston Astros – $530 million
27. Miami Marlins – $500 million
28. Oakland Athletics – $495 million
29. Kansas City Royals – $490 million
30. Tampa Bay Rays – $485 million