Another fixture in the United Rugby Championship disrupted by Covid is the Dragons and Cardiff game. This will also be rearranged, along with Glasgow's trip to Edinburgh on 2 January.
A URC statement read.
"The URC Medical Advisory Group has liaised with the medical teams at Cardiff, Dragons, Glasgow Warriors, Ulster and their respective health authorities and deemed that these fixtures cannot go ahead as scheduled,"
"The United Rugby Championship will now consider available dates to reschedule these games."
🔈𝙋𝙤𝙨𝙩𝙥𝙤𝙣𝙚𝙢𝙚𝙣𝙩 | 𝙐𝙡𝙨𝙩𝙚𝙧 𝙫 𝙇𝙚𝙞𝙣𝙨𝙩𝙚𝙧
The @URCOfficial has confirmed that our Round 9 fixture v @leinsterrugby, due to be played this Saturday, is one of three #URC games this weekend that will not go ahead as scheduled.
Full details ⤵️
— Ulster Rugby (@UlsterRugby) December 29, 2021
Covid also had an impact on Ulster and Leinster’s St Stephen’s Day fixtures against Connacht and Munster respectively.
Leo Cullen's Leinster side returned to full training on Tuesday following positive cases in the camp and have not taken to the field since their Heineken Champions Cup mauling of Bath on 11 December.
Next month's home game against the Emirates Lions was also rescheduled, leaving Leo Cullen's side without a game for five weeks.
Ulster face Munster on the 8th January.