The 24-year-old midfielder opened the scoring for the Magpies just before half-time with a sumptuous goal from distance but there was little else for Guthrie to enjoy following five second-half Fulham strikes to inflict defeat upon Newcastle.
Speaking to reporters after the game, Guthrie said: “Well you should never put yourself in that position and there was a 20 minute period where it was just unacceptable.
“They were getting in behind us too easy, bringing it down too easy. It was really disappointing.”
Newcastle shot themselves in the foot early in the second half as Davide Santon was adjudged to have fouled Damien Duff in the area after a clumsy challenge, as Fulham embarked on a period in which they scored three goals in 20 minutes to completely turn the game around.
“I didn't think the first one was a penalty. But it's still 1-1 and we've gone and conceded in the next 5 minutes,” Guthrie said.
The key for Fulham was the introduction of Andrew Johnson for Steve Sidwell and Chris Baird for the disappointing Bryan Ruiz and a consequent change of shape. Newcastle reacted by altering to a more recognisable 4-4-2 formation but Guthrie refused to blame the tactical switch for the west London side's comeback.
“I don't think the formation had anything to do with it,” Guthrie added.
“I think first half was as well as we'd played away from home.
“Obviously second half we went 4-4-2 not long into it but I don't think that had much to do with it [the result].”
Given the opportunity Newcastle had to move into fifth place with a win at Craven Cottage, the result was as much damaging as it was disappointing.
Guthrie spoke of Alan Pardew's reaction: “There were words said and rightly so.
“It's just so hard to take after being so in control after the first half.
“We didn't know the Chelsea score but we were aware we could be fifth on Monday which was obviously a big target for us.
“It was a 20 minute period and we haven't done that all season.
“It's the first time we've come off and the dressing room has been like that.
“So we'll go away, clear our heads and get ready for the FA Cup [away to Brighton on Saturday].
“There's positives from this game but you look at the scoreline and it tells the story."
Despite scoring for the first time in the Premier League since December 2008, Guthrie had no time to reflect on the quality of his goal nor the time that had elapsed since his last strike for the club.
“It feels a long time ago,” he said.
“But we have to look at ourselves and the goals we conceded. They were far too easy and that's not like us this season.
“It was just a disappointing day all round.”
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