It was far from a great performance, as Roma needed a Chris Smalling header and Paulo Dybala hurt himself while taking a penalty to squeeze past a Lecce side down to 10 men for over an hour.
The Giallorossi dropped Tammy Abraham again and missed Zeki Celik, Rick Karsdorp and Georginio Wijnaldum, while Lecce finally gave Samuel Umtiti his Serie A debut after the summer loan from Barcelona.
It took just six minutes to break the deadlock, as Pellegrini floated a cross from the right to the back post, where Chris Smalling towered above Gendrey to nod in.
There was almost a second moments later, Nicolò Zaniolo flashing an effort across the face of goal just beyond Andrea Belotti and Smalling flicking the Pellegrini assist wide on the rebound.
Just as Lecce were trying to get back into the game, Hjulmand was shown a straight red card for a late and high tackle on Belotti. The referee originally hadn’t even shown a yellow card, but changed his mind after a VAR review. It was certainly clumsy, but the red was perhaps harsh.
Lameck Banda burst down the left and rolled across for Assan Ceesay, whose tap-in was blocked by Gianluca Mancini, and another of his runs prompted the corner from which 10-man Lecce equalised, Gabriel Strefezza smashing in from 10 yards through a sea of legs.
Zalewski’s left-foot screamer stung Wladimiro Falcone’s gloves, then Kristoffer Askildsen made a decisive last-ditch tackle on Zaniolo who had been sent clear by Paulo Dybala.
Rui Patricio took the sting out of an Askildsen free kick and Jose Mourinho threw on Tammy Abraham and Leonardo Spinazzola for the second half. It paid off immediately because Abraham had his heel clipped by Askildsen when turning in the box and Dybala converted the penalty. However, La Joya also injured his left thigh while taking the spot-kick and had to limp off.
Zalewski completed a give-and-go with Abraham to test Falcone at the near bottom corner, and Abraham’s turn and strike was deflected off target.
Federico Di Francesco had a pop from distance and Belotti’s header deflected over by Gendrey, while Di Francesco’s header from a corner was straight at Rui Patricio.
Falcone flew to slap an Abraham diving header away in the final minutes, then the England international had the ball in the net, but only after Pellegrini was offside on the cross.
In stoppages, Eldor Shomurodov wasted two counter-attacks, with Abraham unable to turn in the rebound on the second.
Roma 2-1 Lecce
Smalling 6 (R), Strefezza 39 (L), Dybala pen 48 (R)
Sent off: Hjulmand 22 (L)
VAR decided red card. Funny