The meeting of two European juggernauts, who have reached four of the last five Champions League finals between them without lifting the trophy, was as bruising and tight a match as could be expected between sides renowned for their intimidating defences.
Trailing to Sergio Aguero's 19th-minute goal, Schalke needed help from the VAR in scoring two penalties during a chaotic seven-minute span at the end of the first half.
In one of the round of 16's marquee matchups, Atletico Madrid faced down old foe Ronaldo and kept pushing forward until the dam finally broke in the 78th minute.
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Intermediate-range weapons were seen as especially risky because they reach their targets much faster than long-range missiles. Putin said the USA accusations were "unfounded" and were used to " justify (America's) withdrawal from the treaty".
Coach Massimiliano Allegri, whose side went close to overhauling a bigger first-leg deficit against eventual champions Real Madrid last season, also insisted the tie was far from over.
"It's not a nice gesture, I admit, but I felt the need to do it", he said. "We have to remember we are facing a team who are very good in defence and very risky from set pieces and have done very well in Europe in recent years".
'We got the approach wrong in the second half - it's that simple.
When you shout something abusive, even in a "funny" way, at a stand up comedian then there's a very good chance that you are about to be "destroyed" by them, as they often point out it's literally what they do for a living.