When to Bring the Infield In


By Jim Koerner


In 2001, with the infield drawn in, the New York Yankees lost the World Series on a broken bat single that barely glided beyond the infield dirt. While Yankee manager Joe Torre’s options may have been limited in this particular situation, knowing when to bring the Infield In can have game changing repercussions. There are numerous factors to consider when making these decisions. Let’s examine what these look like.

What do the analytics say?

Sports Information Solutions reports that from 2015-2018 (MLB) with the Infield In batting averages on ground balls and short line drives was .366 with 49% of the time at least one run was scored. In contrast, normal depth on similar ground balls and short line drives yielded a .296 batting average with 63% of the time at least one run was scored. These numbers were based on late game situations with less than two outs and runners on either second and third or just third base. As you can see, batting averages, and thus on-base percentages, drop significantly with the infield back, but it also yields a 14% greater chance to give up a run. So when is the trade-off worth it?

Standard usage of an Infield In defensive positioning

All infielders are brought to the front edge of the infield grass with the sole purpose of stopping the runner from third base from scoring on a ground ball. Typically, this is a late game situation (8th or 9th inning) with either zero or one out. It should be deemed that if the runner on third base was to score, the outcome of the game will be directly affected. In most cases, the potential runner on third base represents either the tying, go ahead, or winning run.

What inning is it and what’s the score?

If it’s early in the game, your team has time to score. As you get deeper into the game those opportunities become more limited. The score may be the biggest determinant. If you are winning by more than one run at any point in the game, there is no need to bring the Infield In. Outs become more important as well as limiting any chance of a big inning from your opponent. In contrast, if your team is behind, you may want to prevent more runs from scoring by bringing the Infield In.

Is there a difference in strategy with a runner on third compared to runners on second and third?

By bringing the Infield In with runners on second and third, you must think about your probability of winning if the runner from second also scores. Keep in mind that if your Infield is In, the runner on second can now get a bigger lead. This nearly guarantees him scoring on a single. If you’re the visiting team in the bottom of the 8th or 9th inning with runners on second and third, it may be wise to only bring the Infield In if the runner on third represents the go ahead or winning run. In contrast, if you’re the home team in the top of the 8th inning with the score tied, you still have two innings left to hit. This might change your strategy. Now you may want to consider factors, such as where you are in the lineup and who is on the opponent’s mound.

Is there a difference with no one out or one out?

This is another very important factor. Playing your Infield In with no one out takes on greater risk than with one out. “The Book” states that with no one out and a runner on first base, the run probability almost doubles (.95) as opposed to one out (.57). This means that if the batter reaches first base, the likelihood of giving up another run in the same inning is significantly higher with no one out. With one out in the inning and a runner on first base, a ground ball double play gets you out of the inning.

Who’s pitching?

This can help you determine how early in the game you may want to adjust your infield. While it may be discouraged to bring the Infield In too early in the game, let’s look at how the pitching match-up might affect this. If the opponent’s pitcher is challenging to score on, trying to save a run earlier in the game might be the difference between winning and losing. If you feel that scoring on the opponent’s pitcher is conceivable, it may be a good idea to play back and get outs.

The type of pitcher you have is important to consider, as well. Does your guy typically induce a lot of ground balls? Have the batters been overmatched at the plate? Recognizing these qualities can help in the decision making process throughout the game. Also, knowing if there is a pitching mismatch can influence what you may decide as a coach. If you believe you have a decided advantage on the mound, why give your opponent the opportunity to have a big inning early in the game? Standard depth would be the best option in this situation.

How confident are you in your offense?

The weaker your offense, the more important it is to prevent runs. This can affect how early and often you try to cut the run at the plate. In contrast, if you have faith that your team will sufficiently score, the risk and reward analysis changes. In this case, have confidence in your offense and play standard depth until the situation becomes more critical.

Is a 5-man infield an option?

In today’s world of extreme shifts, advanced scouting, and precise analytics, this might be the next wave of run prevention. While we have seen it several times at the MLB level, the implementation of a five-man infield takes on great risk. A five-man infield, where an outfielder is pulled in to play infield, should only be implemented if the runner on third represents the winning run in the bottom of the ninth or extra innings. If this is a strategy you wish to apply, there are several factors you should consider. First, does my pitcher give up more ground balls or fly balls? Is the batter a ground ball or fly ball hitter? For positioning purposes, does the batter have strong pull tendencies, or does he spray the ball over the field? The following is a scenario where the risk might be worth taking. It is the bottom of the ninth inning in a tied game. There is a runner on third base and no one or one out. On the mound, is a right-handed sinker ball pitcher that, based on the spray chart, would have difficulty elevating. At the plate, is a right-handed hitter with a two to one ground ball to fly ball ratio and limited power potential. What would you do?

Summary

Obviously, the key to winning baseball games is scoring more runs than your opponent. When done correctly and strategically, bringing your Infield In can be a valuable tool in preventing runs from being scored. When ultimately making the decision, it should depend on the urgency of preventing that run from scoring. Consider your knowledge of the score, inning, opponent, and your own team’s ability when doing so. Put your team in the best position to win by making the right call!

*All of the above scenarios are based independent of the intentional walk. Intentionally walking a batter can significantly change game strategy.



Jim Koerner is currently the Director of Player Development at USA Baseball. Koerner has 21 years of college coaching experience, including 18 years at the D1 level. He spent 13 years as a college head coach, with ten as an NCAA D1 head coach. Koerner has coached over 30 MLB draft or professional Free Agent Signees, 11 All-Americans, 4 Conference Players of the Year, 4 Conference Rookies of the Year, 2 Conference Pitchers of the Year, and over 60 All-Conference selections. Additionally, Koerner is a 2x Conference Coach of the Year and 2021 Mid-Eastern Athletic Conference Southern Division Champion..