Buttler took the wicketkeeper's spot when his Somerset teammate was axed for Wednesday's series-sealing defeat to India in Mohali, the Sun reports.
Speaking ahead of Sunday's fifth one-day international in the picturesque Himalayan town of Dharamsala, the right-hander revealed his county chum took it well.
Buttler said it is never ideal as Kieswetter is a really good friend of him but that is the nature of professional sport, adding there are 11 places in the England side that everybody wants.
Buttler added Kieswetter was obviously going to be a bit disappointed, that's natural, but it wasn't awkward at all and as he's a good friend he'll always give me advice, adding that his friend wished him good luck too. (ANI)