- Manchester United hold defending champions Bayern Munich to a 1-1 draw in England
- Barcelona draw 1-1 with visiting Atletico Madrid at Camp Nou
- Return legs next week
- PSG host Chelsea on Tuesday while Borussia Dortmund travel to Real Madrid
It was honors even when the opening legs of this year's Champions League quarterfinals took place on Tuesday.
The games between Manchester United and Bayern Munich, and Barcelona's all-Spanish duel with Atletico Madrid, both ended 1-1.
In England, the 2012-13 league winners opened the scoring through Nemanja Vidic only for Bastian Schweinsteiger, who was sent off late on, to draw the defending champions level.
In Barcelona, the four-time European champions trailed to a stunning Diego strike before Brazil's Neymar leveled with 19 minutes left to play.
Little fancied before the match, Manchester United may well be the happiest of the sides after surviving a first-half onslaught before taking the lead through Vidic's outstanding header after 58 minutes.
Despite being on the back foot for much of the first hour, the home side could have taken the lead even earlier only for Danny Welbeck to waste a glorious opening late in the first half.
As Manchester United reveled in their unexpected lead, Bayern hit back through Schweinsteiger who lashed home at the end of a sweeping Bayern move.
The midfielder will miss the second leg following his second yellow card, while Javi Martinez also picked up a booking that rules him out of next Wednesday's match in Germany.
"We've given ourselves a great chance (to go through)" said United coach David Moyes. "There was a real determination tonight to make sure we did well."
Missing the injured Robin van Persie and with Juan Mata cup-tied, United made light of recent disappointments as they delivered one of their most impressive performances of the season.
However, they must score next week in Munich -- where the hosts are bidding for a third Champions League final in four years -- to avoid going out on away goals.
Bayern enjoyed nearly 75% of possession at Old Trafford, where the visitors felt Antonio Valencia could also have earned a second yellow card following an untidy challenge on Jerome Boateng.
"Manchester United have a very good team," said Bayern winger Arjen Robben. "I didn't like the atmosphere before the game with everybody saying we would win easily - that is not how football works."
"Missing Schweinsteiger and Martinez is a big blow, but Dante is coming back into the team next week."
In Barcelona, Atletico Madrid showed the qualities that have taken them to the top of La Liga as they ground out their fourth draw of the season against Gerardo Martino's side.
An early replacement for star striker Diego Costa, who had been an injury doubt before the game and limped off with a hamstring problem after 30 minutes, namesake Diego opened the scoring with a sensational strike after 56 minutes.
But just like Manchester United, Atletico's lead was short llived as Barca hit back from Neymar following an exquisite pass from Andres Iniesta.
Barcelona will be without defender Gerard Pique for the second leg, as well as the Copa del Rey final against Real Madrid on 19 April, after suffering a hairline fracture in his right hip, the club said.
The Spanish international is expected to be out for four weeks after falling awkwardly in the opening stages of the match, with Pique going off after just 12 minutes.
"I am full of pride in the way in which we played. If we continue like this, there are chances for success," Martino told the website of European football body UEFA.
"After [Atlético's] goal you saw the best of Barcelona. We played as a team and added a lot of intensity. The tie is finely balanced."
In their four games this season, with Tuesday's clash being their maiden meeting in Europe, Barca and Atletico have registered two goalless and two 1-1 draws.
The visitors protected their unbeaten record in this year's competition, even though coach Diego Simeone was taking his side into one of its fiercest tests.
"We have a team with huge heart and it made me so happy to be able to compete against these opponents," Atletico boss Simeone told UEFA.com. "The Vicente Calderón will be bursting with atmosphere (in the return leg)."
The two teams lead La Liga, with Atletico just a point above their illustrious opponents -- with Real Madrid two further points behind.
The return legs of both games take place on April 9.
On Wednesday, the remaining quarterfinals begin as Paris Saint-German host Chelsea while Real Madrid entertain Borussia Dortmund.