MANAUS, Brazil – The United States team defended Graham Zusi on Sunday after the midfielder came under criticism for his "slow substitution" in the closing stages of the team's emotional 2-2 draw against Portugal.

Former national team forward and commentator Taylor Twellman claimed the length of time Zusi took to walk to the sideline when replaced by defender Omar Gonzalez caused one "extra minute of time" to be added to the end of the game. Portugal sub Silvestre Varela scored with a header in the fifth and final minute of injury time.

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Zusi admitted he had trotted slowly over to the bench, a common tactic from players whose team is leading late in games.

"It is a little bit of gamesmanship I guess, nothing that anyone else wouldn't do," Zusi told Yahoo Sports. "But yeah, of course. You try to put yourself as far away from the bench as possible and make your way over."

Twellman claimed that the fourth official, standing on the sideline, had originally shown on his board that four minutes would be added, but changed it to five "when [Zusi] walked slowly."

An official holds up a sign signaling added time as head coach Jurgen Klinsmann speaks to Graham Zusi. (Getty) More

However, the number on the official board is merely a guideline as to the minimum additional time, not an exact number. "Four" minutes on the board could turn out to mean four minutes and 59 seconds. "Five" minutes could mean five minutes flat, depending on the referee's interpretation.

Zusi's teammates were quick to absolve him of any blame.

"I think so," said goalkeeper Tim Howard, when asked if Zusi had done the right thing by making a slow walk to the bench. "You have to kind of balance it. You don't want to take too much time but you have to take enough to run the clock down."

Former World Cup referee Brian Hall, head of the U.S. Professional Referees Organization, told Yahoo Sports that it would be highly unusual for a full additional minute to be added to compensate for the slowness of a player's substitution walk.

"The referee will convey to the fourth official the minimum amount of time he is expecting to add because of various stoppages in play," Hall said via telephone. "He would usually add some time for a substitution and he may increase that if he feels the player is taking longer to try to delay the game. Typically you are looking at 30 seconds to a minute for a sub; that is the usual guideline."

Therefore, it is entirely possible that the mere fact that a replacement was being brought onto the field, rather than the time taken by Zusi, led to the change on the board.

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Also, it is important to note that the "additional time" is merely to make up for the stoppage – it does not add extra time where the ball would be in play and therefore give an attacking team extra seconds with which to score.

"I think they add 30 seconds for every sub they do so I'm not really too sure about that one," Gonzalez said when questioned on Twellman's comment.

Central defender Matt Besler laughed when he heard Twellman's assertion. "I don't know, I'm not going to comment on that," he said. "That's his opinion."

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