Celtic's 2-0 victory over Hibernian assured Motherwell of entry to the UEFA Cup.
McGhee took charge last summer after Motherwell avoided relegation on the penultimate day of the season despite losing at home to St Mirren.
McGhee insists he has performed no magic trick - just encouraged the players to show their quality.
"The fact is it is not a miracle as these boys are good enough," McGhee said.
"They have been good enough to beat Aberdeen three times, they have beaten Dundee Utd and Hibs really well, we have won at Parkhead and taken points off Rangers.
"They have proven over the season to be good enough and all I have done is brought that out and encouraged it.
"(Assistant manager) Scott Leitch has been a superb lieutenant this year for me. We have worked as a team all of us and we all deserve equal credit."