I'm a big fan of sports, particularly baseball.

I don't know what made me fall in love with the game. My mother was from South America, and my father never played sports (or took me to any games).

But it always appealed to me.

It could be all of those summers spent at home by myself, watching the Chicago Cubs on WGN or the Atlanta Braves on TBS while my mother was working.

Maybe it was the fundamentally American nature of the sport. (It is called America's pastime, after all.)

Or it could be the incredible strategy underlying the sport that’s barely evident to a casual viewer.

For whatever reason, I became an avid student of baseball and have attended close to 800 games in seven different countries.

And through watching baseball all these years, I’ve also learned a lot about the game of life – and investing.

With baseball season in full swing, I wanted to share a few principles of the sport that apply directly to the stock market.

1. Hit the ball where it's pitched.

This is one of the sayings I have repeated the most in my investing career.

I often talk about selectivity in making your trades or investments.

To outperform the markets, you need to find the best opportunities available. If you were playing the averages, you could buy an index fund and be done with it.

Of course, it is possible to outperform the markets, and the key is being selective.

Along with selectivity, you must take what the market is giving you, not what you want it to give you.

To a certain extent, my approach to trading is precisely what they talk about in baseball. I only look to take what the markets give us.

There are always good pitches in the market. You just need to figure out when (and how) to swing the bat.

2. Trends persist.

This one comes from Tony La Russa, one of the most excellent baseball managers of all time.

La Russa believed that trends (or hot and cold streaks) constantly emerge in baseball.

The best bet is to follow them until they demonstrate they are not working. Sure, they can be painful when they stop working, but streaks can go on for a long time.

You can make a lot of money if you are disciplined in identifying the streaks and following them until they change.

I had never given much thought about that as it relates to baseball, but I think about it a lot in investing.

One of my main rules when it comes to trading is to look for trends, not only in stocks but also in a company's operational performance.

Specifically, I look for stocks that have been long-term winners, are beating Wall Street's expectations, and have a history of growing their businesses.

The key in the markets is identifying the trends and figuring out how to capitalize on them appropriately.

3. Focus on the approach, not the outcome.

This is another way of wording the saying "Plan the trade, trade the plan."

Outcomes, both in baseball and investing, are uncertain.

My job is to develop a plan and methodology to help me determine where to find the best opportunities. But even those can fail sometimes.

If you have a good plan on how to deal with the outcomes – positive or negative – you will ultimately succeed with a winning strategy.

Even if you fail half the time, whether in baseball or in the markets, a solid approach means you can still win.