"I'll accept it because I know I make a mistake," Pineda said. "That's it."
Pineda was ejected by home-plate umpire Gerry Davis in the second inning of New York's 5-1 loss, after Red Sox manager John Farrell asked Davis to inspect a suspicious brown substance on the right side of Pineda's neck.
Pineda later admitted that he had applied pine tar to his neck after allowing two runs in the bottom of the first inning, saying that he was having difficulty controlling his pitches and that he did not want to hit any batters on a cold evening.
"I tried to put it on my neck, just a little bit," Pineda said. "I made a mistake again and put in too much, and everybody sees it. It's my mistake, you know? I feel so sad and I feel bad for that."
Rule 8.02(b) says a pitcher shall not "have on his person, or in his possession, any foreign substance. For such infraction of this section the penalty shall be immediate ejection from the game. In addition, the pitcher shall be suspended automatically."
Pineda's suspension will be with pay; by contrast, suspensions for performance-enhancing drug use are without pay. The Yankees must play with a 24-man roster until Pineda's suspension is fully served.
He will be eligible to return on May 5, when the Yankees open a series with the Angels in Anaheim.
"I think he got caught up in the moment of competing," manager Joe Girardi said. "I think he understood [the consequences], but he got caught up in the moment of competing and it got the best of him."
Pineda confirmed that he touched his neck to apply pine tar to the ball on Wednesday. Farrell interrupted Pineda with a 1-2 count on Grady Sizemore, an at-bat in which Pineda appeared to go to the pine tar spot.
The Red Sox also spotted pine tar on Pineda's pitching hand in an April 10 start at Yankee Stadium, but they did not bring it to the attention of the umpiring crew. This time, Farrell said that he could clearly see the smudge from the first-base dugout.
"I felt like it was a necessity to say something," Farrell said. "You know, I fully respect on a cold night you're trying to get a little bit of a grip. But when it's that obvious, something has got to be said."
Though it is violation of Rule 8.02, numerous Major League pitchers are known to use pine tar, sunscreen or other substances to help gain control of their pitches.
Mike Napoli and A.J. Pierzynski were among the Red Sox players who said that their issue was not with the actual pine tar use, but with Pineda's lack of tact in hiding it.
"I don't have a problem with guys that do it," Pierzynski said. "I know as a hitter, I want to get in there and know the guy has a grip, especially [Wednesday] when it was cold and windy.
"Put it on your hat, put it on your pants, your belt, put it on your glove -- whatever you have to do. You just can't do it that blatantly. That was what the biggest issue was. No one has an issue with him doing it; it's just more of the fact that it's so blatant."
Girardi said that the fact that opponents seem to be accepting of pine tar use, as long as it is not obvious, suggests that it may be time for a revision of Rule 8.02.
"That is kind of strange, isn't it?" Girardi said. "It makes you wonder if people understand that there is something wrong when it's cold and it is hard for people to grip a baseball. ... I'm sure I'll have a conversation [with MLB] at some point."
Because of a scheduled team off-day on April 28, Pineda will effectively miss one start. David Phelps, who relieved Pineda after Wednesday's ejection, is a leading candidate to make that start.
"Obviously, it does affect us," Girardi said. "We'll talk about that. There's some candidates we can use from in here; I just haven't had a chance to share it with them."
Pineda said that he apologized to Girardi, pitching coach Larry Rothschild and others in the Yankees' clubhouse about the situation.
"I said sorry. I feel so bad," Pineda said. "I apologized to the teammates and everybody. I know I made a mistake. Now I'll learn from the mistake and put everything in the past now."
Pineda joins a handful of Major League pitchers who have been suspended for pine tar use in the past decade. The Rays' Joel Peralta was penalized eight games in 2012, the Angels' Brendan Donnelly received 10 days in '05 and the Cardinals' Julian Tavarez received 10 days in 2004.
The suspensions of Donnelly and Tavarez were cut to eight days after appeal, and Peralta dropped his challenge with no reduction.
In response to Pineda's ejection, the Yankees shuffled their roster prior to Thursday's game, restocking their bullpen after using four relievers to soak up the remaining 6 1/3 innings of Wednesday's contest.
Right-handers Bruce Billings and Shane Greene were added from Triple-A Scranton/Wilkes-Barre, while infielder Dean Anna and right-hander Preston Claiborne were optioned from Triple-A.
"It's important that we move on, because the game of baseball does not stop," Girardi said.