Harrison, July 23 A New York Red Bulls team made up of mostly developmental third-division players scored four second-half goals and stunned Chelsea 4-2 on Wednesday night in the English Premier League champions’ first game on their US pre-season exhibition tour. Sean Davis scored twice and Franklin Castellanos had a goal and an assist to help the team with only four players who have any minutes in MLS this season upset the 2012 European champion and five-time English league winners. “I was surprised by our fragilities,” Chelsea manager Jose Mourninho said. “I said before we have no fragilities, but today we had fragilities, lots of fragilities. I was surprised that we were not good enough in the second half to cope with that,” he added. “We hit the post two or three times, I don’t know, but they’re young guys, they have quality, and motivation, their motivation is really high to play against us.” Loic Remy gave Chelsea the lead midway through the first half, but Castellanos tied it in the 51st minute, 16-year-old Tyler Adams added a header and Davis tacked on a pair to rally New York and stunned the near capacity crowd of 24,076 at Red Bull Arena. This is the third time in four years Chelsea have toured the US before beginning their season and the second time they have competed in the International Champions Cup with several other top European clubs. Using a starting lineup of several regulars and three players returning from loan, the Blues had the better possession and chances, outshooting the Red Bulls 12-4 in the first-half. Remy, who scored seven goals in 19 league appearances last season, gave Chelsea the lead when the Blues caught the Red Bulls on a counter. Substituting liberally to begin the second half and inserting Eden Hazard, John Terry and Nemanja Matic, Chelsea continued to dominate the second half. But Terry’s miscue that enabled New York to tie the match. Castellanos raced after Terry’s weak back pass to substitute keeper Asmir Begovic, who tried to clear the ball with a slide tackle, won the ball and scored into an open net. Chelsea continued to push forward and Diego Costa put a header off the post in the 62nd, but Castellanos curled a cross into Adams at the six, who headed it in 7 minutes later. Davis latched onto a loose ball at the top of the area to increase the Red Bulls lead to 3-1 in the 73rd, before Hazard settled a free kick at the top of the area and scored in the 75th to raise English hopes. But Davis corralled an errant clearance attempt by Ramires at the top of the Chelsea area in the 77th and scored again. Red Bulls used a developmental roster after playing and losing on penalties on Tuesday to the Philadelphia Union in the US Open Cup quarter-finals. Chelsea will play Paris Saint-Germain on Saturday and Barcelona on July 29 before returning to England to play in the Charity Shield against Arsenal on August 5. They will begin the English Premier League season on August 8.