When a baseball player wins a championship or switches teams fans are more likely to buy his jersey.

That’s the lesson we can take away from the list of bestselling jerseys at MLB.com from this offseason, which is measured from October 31, 2013 to March 30 2014.

The biggest seller was Boston Red Sox’s slugger David Ortiz, whose number 34 Majestic jersey was up 932 percent from the same time period last year. His teammate Dustin Pedroia took the second spot, with his sales up 379 percent.

Jacoby Ellsbury, Robinson Cano and Prince Fielder all changed teams this offseason and made the top 20 list.

Rookie Yasiel Puig was also in the top 20, as were young stars Mike Trout, Manny Machado and Bryce Harper.

You can see the entire list below. So don’t buy any of these jerseys if you want to be original.

20. Jacoby Ellsbury New York Yankees
Move to the Bronx has triggered run of jersey sales.

19. Yu Darvish Texas Rangers
Japanese import is popular on both sides of the pacific.

18. Koji Uehara Boston Red Sox
So is post-season hero Uehara.

17. Adam Wainwright St. Louis Cardinals
The perennial Cy Young candidate is also a hit at the sporting goods store.

16. Prince Fielder Texas Rangers
Switching teams is a good way to generate jersey sales.

15. Matt Harvey New York Mets
Mets fans wish they could swap their Harvey jersey for the real thing.

14. Mike Trout Los Angeles Angels
Baseball’s best player only 14th in jersey sales.

13. Miguel Cabrera Detroit Tigers
To be accurate, you have to buy it in XXL.

12. Bryce Harper Washington Nationals
Eye black sold separately.

11. Yasiel Puig Los Angeles Dodgers
It’s no surprise the Cuban sensation sold some jerseys.

10. Manny Machado Baltimore Orioles
Machado tops Trout and Harper in jersey sales.

9. Robinson Cano Seattle Marines
Another team changer pops up on the list.

8. David Wright New York Mets
We’re thinking a lot of wannabe Mrs. Wright’s purchased a Mets #5.

7. Buster Posey San Francisco Giants
The clutch catcher has certainly earned his popularity.

6. Andrew McCutchen Pittsburgh Pirates
Win an MVP and suddenly everyone wants your jersey.

5. Clayton Kershaw Los Angeles Dodgers
Dodgers hope the left hander’s jersey will be relevant for years to come.

4. Yadier Molina St. Louis Cardinals
St. Louis fans again show they know their stuff by buying Molina gear.

3. Derek Jeter New York Yankees
Something tells us they’ll let you buy Jeter jersey after he retires.

2. Dustin Pedroia Boston Red Sox
The Laser Show is a hero to normal-sized humans everywhere.

1. David Ortiz Boston Red Sox
Big Papi is Numero Uno when it comes to jersey sales.