You can get negative expected Xg yes, and based on the stats DCL is the worst striker in the league since the start of last season. Last season he scored 6 less goals then the shot data suggests he should have.
Even this season he has an expected goals figure if 3.8 and has scored two, which again is the worst conversation rate this season. Which if you look at players with similar Xg, Delap has had a Xg of 3.6 and has scored 6 even Mateta who is having a poor season has had an Xg of 3.3 and scored 3.
He has had enough chances, he needs benching.
Find out who underperformed their expected goals by the largest margin this season
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