In Pittsburgh on Sunday, Pirates third baseman Jung Ho Kang saw Bryce Harper motoring toward third with a clean triple, even as the throw from right fielder Josh Bell soared above two relay men and wide of the base. Faced with the possibility of Harper scoring on the overthrow, Kang did what he thought necessary—he applied a phantom tag.

Such a play, known as a deke (short for “decoy”), has long been a staple of major league baseball. In it, a fielder acts as if a play he has no chance of making is in front of him, so as to slow or stop a runner who might otherwise advance to the next base. The most prominent deke ever came during Game 7 of the 1991 World Series, when Twins second baseman Chuck Knoblauch helped prevent Atlanta’s Lonnie Smith, at first base, from scoring on a double into the gap by pretending the blast never left the infield. Such a ploy can only work if the runner has no idea where the ball actually is, of course, but in that instance Smith did not. The run he failed to score cost his team dearly in a 1-0 loss. (The incident is discussed in depth in The Baseball Codes.)

The play was totally legit, and was likely the difference in Minnesota’s victory. However, it is not the type of deke we’re discussing today.

There is a difference between Knoblauch’s deke—and the panoply of plays like it that are seen around baseball all the time—and what Kang did to Harper. Smith paid no price outside of tarnished pride and a run off the scoreboard. Harper, however, was not so lucky. That’s because Kang’s decision to throw his glove down came so late in the play that the runner had no choice but to force himself into an ill-timed and awkward slide. (Watch it here.)

Such a play was described in The Baseball Codes:

A number of players have been injured by ill-timed or unnecessary dekes, which leads to an unwritten rule about when it is and isn’t appropriate to use the maneuver. Infielders throwing down phantom tags at the last possible moment can cause awkward slides, and the potential for damage is very real. “If a guy is stealing, you don’t pretend the throw is coming,” said second baseman Craig Grebeck. “If he’s coming in standing up and you all of a sudden look like the catcher is throwing the ball, a late slide can tear up an ankle or a knee.”

That’s exactly what happened to Gene Clines in 1973. Clines, a fourth-year outfielder with the Pirates, was on first base in a game against San Diego; with a full count on the hitter, he took off for second. The pitch was taken for ball four, but instead of simply strolling to second, Clines— who never peeked homeward to assess the situation—proceeded full speed ahead. Padres shortstop Derrel Thomas waited until Clines was nearly atop the base, then inexplicably threw his glove down as if a late throw were about to arrive. Clines, flustered, went into a hurried slide and badly injured his ankle. “That play right there cost me a lot of time,” he said, still angry at the thought more than three decades later. “I never fully recovered for the rest of that year.” Clines, batting .291 going into the game, missed three weeks, and hit just .227 in the two months thereafter.

Sure enough, Harper jammed his thumb on the play, and left the game shortly thereafter.

Pertinent point: Gene Clines was a coach under Dusty Baker for six years in San Francisco and another four in Chicago. Now Baker manages the Nationals, and through his close friend knows all too well the dangers of a poorly thrown deke.

Washington pitcher A.J. Cole responded during Kang’s next at-bat by throwing a pitch well behind the hitter at shoulder-blade level. (Whether Baker ordered it is highly doubtful, based on his track record.)

Because Kang ducked as the pitch flew behind him, the pitch looked like it came in head-high. The Pirates took great and understandable exception to Cole’s message, and benches quickly emptied. (Watch it here.)

The dustup served to distract from the far more interesting discussion about the grey area of infield decoys. The clear difference between Kang’s tag and that of Derrel Thomas decades earlier is that there was clear benefit to Kang’s strategy—holding Harper at third. If he could have put down his deke in a timely fashion, giving Harper enough space to undertake a regular slide, it would have been fine.

Kang appeared to have had time to have done this, even after identifying the overthrow. Barring that, however, he still had another option:

Don’t do anything at all. Which is exactly what he should have done.

Update (9-27): Deking is wrong, but drilling is punishable. Cole just drew a five-gamer.