Shevchenko, the former AC Milan and Chelsea striker who has a handicap of two and plays left-handed, plunged to a 12-over-par 84 in the opening round of the Kharkov Superior Cup in his native Ukraine on Thursday.
"He must have had a lot of pressure going in there but he loves the game," former world No 1 Els, a four-time major champion, told Reuters after carding a level-par 71 in the opening round of the PGA Tour's BMW Championship.
"He's a great student of the game, he asks lot of questions and he wants to get better. Golf is his passion. Good for him."
South African Els got to know Shevchenko well after playing several practice rounds with the former Ukrainian international, especially at Queenwood Golf Club in Surrey, when they both lived in England.
Though Shevchenko ended the day 20 strokes behind his pacesetting compatriot Victor Riu in the second-tier European Challenge Tour event, Els felt the ex-soccer player could flourish in an appropriate golfing environment.
"It depends on the golf course," Els said after finishing his own round at Conway Farms Golf Club outside Chicago eight shots behind leader Brandt Snedeker.
"If Andriy has a course where he can reach the par-fives with not too much rough, where it's benign, he can shoot par or better than par.
"He has shot a lot of low rounds around Queenwood, in London, so he can play. But doing it on weekends with the guys and doing it in a tournament is completely different. But you've got to give him 10 out of 10 for effort."
Asked to assess the strengths in Shevchenko's golf game, Els replied: "He's got a great head. He never gives up. He is always fighting. He hits it quite well. He can hit it very straight.
"He hasn't got too many really bad things in his game but obviously it's a long way going from the amateur game to the pro (game)."
Shevchenko, 36, himself agreed that he had succumbed to pressure in the opening round of the Kharkov Superior Cup.
"It's a completely different game when you are under pressure," the 2004 European Footballer of the Year said on the European Tour's website.