no new modification came into play...it already existed
You're wrong here, and I could show it wrong with a highschool experiment. You isolate a bacteria, let it multiply, test for an antibiotic that will kill it, let it grow into a large colony, and then incrementally add the antibiotic to the colony. Unless you're really unlucky, you will soon have a colony resistant to the antibiotic.
As we started out with one bacteria, and the end result has accuired a new property, it's very much evolution.
"You're wrong here, and I could show it wrong with a highschool experiment. You isolate a bacteria, let it multiply, test for an antibiotic that will kill it, let it grow into a large colony, and then incrementally add the antibiotic to the colony. ... As we started out with one bacteria, and the end result has accuired a new property, it's very much evolution." 
No, and no.
No, the bacteria didn't acquire a new property, and no, mere natural selection (without mutation) is not Evolution.
Consider, if you applied an antibiotic to which no member of a colony was immune, the entire colony would *either* have to die or else instantaneously mutate.
Instantaneous mutation never happens in real life. Instead, some existing members of said bacteria colony will already have a trait that makes them resistant to the applied antibiotic. They will then thrive and multiply (no more competition from their now-dead peers, for instance).
Thus, a colony that isn't wiped out soon returns with a widespread resistance to the original antibiotic.
But that effect is due only to Natural Selection, not instantaneous mutation.