London Irish's relegation from the Aviva Premiership was confirmed on Saturday, despite the Exiles not playing.
Worcester's four first-half tries against Sixways visitors Harlequins secured the Warriors a bonus point, putting them 10 points clear of Irish and meaning the Exiles cannot overtake them.
Teams tied on points are initially separated by number of wins, and Irish have three victories less than Worcester. In the end those mathematics did not matter as the Warriors completed a 44-13 defeat of Quins to secure their safety in style.
Irish host Saracens on Sunday, then end their campaign at Bath next weekend, but they will now return to the Championship after just one season back in English rugby's top flight.
Championship title winners Bristol will replace them in the Premiership next term.