With Holliday at first base and none out in the 11th, Jacoby Ellsbury chopped a ball to first baseman Mitch Moreland, who threw to shortstop Xander Bogaerts at second base. Holliday broke back toward first base, sliding feet-first into the bag as Bogaerts attempted to complete a double play. Holliday's explanation was that he assumed Moreland had tagged the bag to take away the force.
"The next step is for us to file a formal protest, which we will follow through on," said Farrell. "It's a 24-hour filing period from the incident."
Assistant general manager Brian O'Halloran will submit the protest on behalf of the Red Sox.
Farrell heard Holliday's explanation, but he is still adamant that it was interference.
"Still firmly believe there was interference on the play. If it goes unaddressed or goes without any kind of further attention brought to it, who's to say [you] can't instruct runners to do the same going forward," said Farrell. "Clearly, I believe it's Rule 6.01, that is interference. By the letter of that rule, that play yesterday was clearly interference.
"If there was no interference, he'd have had access to the bag. He was taken out of it by the returning runner, the retreating runner. There's different components to the rule. Interference has got to be, if the runner is advancing, that takes away the interference. But this is a retreating runner that gets in the way of a player that is trying to complete the back end of a double play. There were a number of things in here that you have to factor in."
Farrell cited that Holliday made a similar retreat in a game against the Brewers several years ago.
"It's a heads-up play on his part, to be honest with you. If you know it's a dead out, retreat to the bag, slide in," said Farrell. "It's not like he was going after anyone with physical intent, but he was in the middle of the play. Say what you want, whether you think it's a tag play versus a force play, but Mitch is eight feet inside the bag when he fields the ball, so a heady decision in the moment, but this has happened before."
Ian Browne has covered the Red Sox for MLB.com since 2002. Follow him on Twitter @IanMBrowne and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.