Anier scored either side of Ainsworth's goal to take his tally for the season to seven and McCall is hopeful their loan deals can be extended, despite money being tight at Fir Park.
"We would like to keep Henri and Lionel - I thought Lionel had his best game for us - we have had tentative discussions with their agent," he said.
"We now need to have discussions with (directors) Leeann (Dempster) and Derek (Weir), but that might just have twisted their arm.
"Without stating the obvious, going out of the cup competitions has not helped the finances so we have to make sure what we do is for the best for the club, but it's not as if we would be breaking the bank."
Wages may prove a sticking point with regard to Viking Stavanger and Estonia striker Anier, while McCall is also keen to tie up a deal with Rotherham for winger Ainsworth.
"We aren't paying his full wages at the moment so that's where the stumbling block could be. If we could pay him the same salary now as we have done then I think we will be able to keep him," McCall said of Anier.
"He had little niggles and has not played a lot of 90 minutes but I thought he was terrific," McCall added in his assessment of Ainsworth.
"He took his goal really well and he's another one who would like to stay, and hopefully we can do that as well."
St Mirren manager Danny Lennon cut a disconsolate figure in contrast after seeing his side fall to their second straight defeat.
"The highly frustrating part is that we have dropped one or two gears in terms of our work ethic, and that has been the main ingredient of our success," he said.
"I just felt we were off, we played second fiddle to a lot of balls and Motherwell just showed a greater hunger.
"That disappoints me and it hurts me to say that."