John Legend Roasted After Covering Nate Dogg's Hook in '21 Questions'

John Legend got onstage with 50 Cent to do his best version of Nate Dogg — and while he certainly dished his own twist … not everybody’s feeling it, and they’re letting him know too.

The singer celebrated his 45th birthday Thursday in NYC — where he and Chrissy Teigen hired Fitty to perform, with the rapper doing his classic “21 Questions” live in front of a crowd. At first, it was just 50 Cent handling the hook and verses … but JL eventually jumped in.

Very impromptu, John grabbed the mic from 50 and started belting out the chorus … singing, “Girrrrl, you seem to love me now // Would you love me if I was down and out.”

Looks like John kept singing while 50 continued to rap — and in the moment, everyone seemed to receive it pretty well … cheering on the bday boy and giving him props.

Unfortunately, it was a bit of a different reaction on the old bird app (now X) … ’cause folks saw this clip and roasted the hell outta John — some kinda meanly, others more lovingly.

You can hop into the trend to see what people had to say … but essentially, the jokes amounted to John sounding more like a church crooner than an R&B stud with his take on the famous hit. As someone put it, “John legend made it sound like a negro spiritual.”

Like we said, it’s all in good fun … but let’s just say his version certainly took people aback.