While Martino accepted his share of the blame for the mauling, the veteran coach pointed the finger at his players, who included high-profile signings Luis Suarez, Sergio Busquets and Jordi Alba.
“There is not much to say, except that we were outmatched from start to finish,” Martino said following the drubbing. “Red Bulls had the desire to win and we had no desire to compete.
“When a team enters a game without the desire to win, without spirit, without competing, and the other side just want to win the game, they are going to win it.”
Martino meanwhile refused to blame the absence of Messi for the loss, noting that the team had produced a 3-1 victory at D.C. United last week without the Argentina superstar.
“The absence of the best player in the world is important for everyone — but last week with D.C. Leo didn’t play either,” Martino said.
Earlier, former Miami player Morgan had run Martino’s side ragged with a brilliant man-of-the-match performance.
Scotland international Morgan, who arrived in Major League Soccer four years ago after stints with Celtic, St. Mirren and Sunderland, fired New York into the lead after just three minutes.
A lacklustre Miami, meanwhile, barely created a chance in the opening 45 minutes, with a curling Suarez shot that flew wide after 27 minutes their most threatening opportunity.
Morgan then doubled New York’s lead six minutes into the second half, pouncing on a clever assist by Dante Vanzeir to make it 2-0.
The Scottish forward was then instrumental in creating New York’s third on 66 minutes, showing tremendous hustle to keep the ball in play wide on the left before squaring into the area.
Vanzeir helped the cross along and Venezuelan forward Wikelman Carmona tucked away the finish.
Morgan completed his hat-trick four minutes later to cap a sweeping New York counter-attack after more good work from Vanzeir.
Vanzeir was involved once more, shrugging off a feeble challenge from Noah Allen down the right flank and then rolling an inviting low cross into he path of Morgan, who made no mistake.
The wins left New York level on 10 points with Columbus Crew and Miami at the top of the Eastern Conference. Columbus are in first place on goal difference, with Miami second.
In other early MLS games on Saturday, New England Revolution won their first point of the season after battling to a 1-1 draw with Chicago Fire.
Nacho Gil’s goal in first-half stoppage time earned a share of the points for the Revs, who had fallen behind to a Hugo Cuypers goal after 20 minutes.
© Agence France-Presse
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