Mariano Rivera is 41 years of age, but he is still playing at an incredibly high level.

Last year, he had an ERA of 1.80 in 61 appearances with 33 saves. In fact, in his last eight seasons, he has only had an ERA over two, just once. That’s pretty magnificent for a guy that was supposed to retire three years ago.

Overall, he has played 16 MLB seasons and has compiled a 2.23 ERA and 559 saves. He also has been to the All-Star game a whopping 10 times. He also has won the AL Rolaids Relief award five times. To top it off, he leads all active pitchers in career ERA and is 13th in MLB history.

However, how long will he be able to keep up the production?

In the past three years, I have noticed a steady incline in his ERA. It obviously has not been a dramatic increase, but it is evident.

Even though he only pitched six less innings in 2010 than in 2009, he threw 27 less strikeouts. It seems remarkable that those are the only numbers that have actually shown signs of age, but it might be enough for me to place a red flag on Rivera.

In fantasy baseball, closer is a deep and also somewhat meaningless position. You can find closers for miles upon miles that are usable.

However, I still expect Rivera to have one more plausible season, in the two ERA range, then another declining season in the tank for an over-three ERA. After that, he retires as his contract is up.

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