Poulter thrives in the biennial event against the United States, winning all of his matches in the 2012 'Miracle of Medinah', where Europe fought back from four points down on a memorable final day.
However, he might not automatically qualify for this autumn's contest at Gleneagles because of his 2014 woes - he has recorded just one top-five finish after finishing second, fifth and second in the final three events of last season.
"I'm a little bit concerned what's happening right now, but not worried," PA quotes McGinley as saying.
"I spoke to [Poulter] for a good 45 minutes on the phone last week and we had a really good chat. He knows he has my support like all the players do.
"He's determined to be there but he has to earn his place. I've said it before and I told him last week, he has to earn his place. He knows that."
If Poulter doesn't get climb back into the automatic qualification spots, he will have to rely on a captain's pick to play at Gleneagles.