A strike by London Underground staff means the game has had to be rescheduled, easing the Hammers' festive congestion a little but adding to another busy spell at the end of the transfer window.
West Ham are dealing with a lengthy injury list at the moment, naming only six subs against West Brom last weekend, but McDonald still thinks they would have been better off playing Arsenal next week.
"I think you can look at it both ways; yes it gives us an extra couple of days to get players back, but it does mean we will have an even busier January," he said.
"We would probably have preferred to play the game and we are slightly disappointed that it has been called off, but we will be ready when the game comes in January.
"After the good performance against West Brom away, keeping a clean sheet, and giving Arsenal a really good game earlier in the season, we were looking forward to going to the Emirates.
"I know they have picked up over the past couple of games but putting them under pressure would have been interesting to see."
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