Dennis Eckersley doesn't like sliding into first base, and the former closer-extraordinaire (and current Boston Red Sox commentator) isn't afraid to let people know it. This season I've heard him criticize more players (primarily Andrew Benintendi) for sliding into first than anyone I've ever heard before.
For those of you who have never played baseball, let me tell you about a certain situation that happens to every single baseball player at some point in their career. At the end of practice one day in Little League, everybody gathers around the coach and he tells you one of the cardinal rules of the sacred game of baseball: never slide into first base.
It's dangerous. It actually slows you down. There is no point.
Sliding into first is a bone-headed move, and will almost certainly result in an automatic spot on the bench. Unless, of course, we're talking about the coach's son, who will be a surefire blue chip shortstop/pitching prospect with a .999 batting average and a 110 mph fastball, destined to be the number one pick right out of high school. In that case, sliding into first base is not just permitted, but strongly encouraged.
The other 99.9 percent of us mere mortals are told that sliding into first is, and will always be, a big no-no. That's a lie: at times, it does make sense to slide head-first into first base, but the reasoning behind it has nothing to do with speed. Secondly, sliding head-first into first base doesn't necessarily slow you down. As a matter of fact, sliding into first base could possibly make you faster.
But only if you literally execute the slide to complete 100 percent perfection. Unfortunately, nobody, not even professional baseball players, are 100 percent perfect (just ask Matt Holliday), so thinking that sliding into first will have any real positive impact on coming out on the right side of a bang-bang play is completely ludicrous.
However, as I said before, that doesn't mean that sliding into first base is never a good move, because sometimes a play at first base isn't about speed. Don't believe me? Take a look at this move from the Pirates' Josh Harrison.
As you can clearly see, Harrison would have been cooked if he had stayed on his feet, but by sliding and thus bringing himself closer to the ground and further from the line, he made it more difficult for Cubs first baseman Anthony Rizzo to apply the tag, which was ultimately the difference between a baserunner and an out. In summary: sliding into first base does make sense if it's to avoid the tag.
So go tell your Little League coach to pound salt.
That being said, Dennis Eckersley isn't crusading against sliding to avoid tags, but rather sliding to gain speed, which we've already decided make no sense. Odds are, they're going to slow you down. Add that to the possible injuries that could result from a slide, and we come to the conclusion that sliding into first, generally, isn't worth the risk, even if you're trying to avoid a tag.
Now, some may be asking themselves, "Well, if sliding into first base is so maligned because it slows you down, why is sliding into other bases widely accepted as the norm? Wouldn't that slow you down too?"
The answer is yes, but in the case of other bases, that could be a good thing. See, first base and home plate are somewhat unique in baseball because you can run right through them without being tagged out. In the case of first base, that means that keeping your momentum going and running straight through the bag will almost certainly get you from point A to point B as fast as possible. And as far as home plate goes, disregard it for now, because almost all slides into home are solely for the purpose of avoiding a tag.
Sadly, the same courtesy isn't applied to second base or third base. Running through them would almost certainly result in you being tagged out. That means that you have to stop once you touch either of those bases. In a vacuum, the no-sliding rule would still apply: sprinting straight from first to second or second to third would definitely be faster than any other alternative, but only if you were capable of stopping on a dime.
I don't know about you, but I definitely can't just stop on a dime if I'm in a full sprint. Actually, I take that back, I may not know about you, but I know physics, and physics says that you can't stop on a dime. Take that, fellow scrub!
Therefore, if you're running to second or third, you have two choices: completely killing your momentum by slowing to a dead stop as you approach the base or sliding, which allows you to maintain at least some of that momentum even after you touch the base. Now the choice seems obvious.
But back to the main point: Dennis Eckersley may look like a hippie, and may come from a generation of baseball that emphasized being tough and getting dirty, but his crusade against sliding into first base is completely righteous.
In most cases, it is totally useless and possibly harmful.
That is, if you're not the coach's son.