first ever league fixture
... that Sheffield United played their first ever league fixture against Burton Wanderers on 13 September 1890?
... that <a href="./Sheffield_United_F.C." id="mwESA" rel="mw:WikiLink" title="Sheffield United F.C.">Sheffield United</a> played their <b id="mwESE"><a href="./Sheffield_United_F.C._league_record_by_opponent" id="mwESI" rel="mw:WikiLink" title="Sheffield United F.C. league record by opponent">first ever league fixture</a></b> against <a href="./Burton_Wanderers_F.C." id="mwESM" rel="mw:WikiLink" title="Burton Wanderers F.C.">Burton Wanderers</a> on 13 September 1890?