Chelsea, seeking to maintain their lead at the top of the table over Manchester City and Liverpool, dominated the first half against a United side playing their first Premier League match under caretaker manager Michael Carrick after Ole Gunnar Solskjaer's sacking last weekend.
The Blues were punished for failing to turn possession into goals five minutes after the restart when United cleared and Jorginho, alone near the half-way line, miscontrolled and Sancho raced past him to beat the helpless Edouard Mendy. Chelsea were rocked by the goal against the run of play but Jorginho repaid his debt to the Stamford Bridge faithful in the 69th minute when he coolly converted a penalty after Aaron Wan-Bissaka fouled Thiago Silva. The hosts pushed for a winner and brought on Romelu Lukaku, returning from injury as a substitute for the last 10 minutes, but they failed to find a way through United's defence.
The result leaves Chelsea top of the table, a point ahead of Manchester City and two clear of Liverpool. United sit in eighth place, 12 points behind Chelsea.