"Manu is the best goalkeeper in the world, maybe the best ever," said Guardiola by way of explanation. "But he's played every game. Sometimes your head needs a rest too."
Guardiola: 'Experience and character'
That left Bayern with Reina and Tom Starke in Bremen, and while Guardiola stated that "both have a lot of experience and a great character", it was Reina who got the nod from kick-off. The Spain international joined Bayern in July 2014 and would perhaps have made his Bundesliga bow earlier had he not injured his calf in a friendly in October, forcing him to the sidelines for several weeks.
Nevertheless, he was a composed presence between the sticks right from the off and dealt with Bremen's rare incursions forward with minimal fuss. The only time it looked like the 32-year-old might be caught out was early in the second half when Fin Bartels tried an audacious lob from distance, but Reina scurried back in time to tip the ball over, ensuring he kept a clean sheet on his maiden Bundesliga appearance.
Reina: 'Our mentality was really good'
"I was always ready to get my opportunity and it was a pleasure to play alongside players like these," said Reina after the final whistle. "We were expecting a really tough game, which it was in the end, but the mentality, the approach and the character of the team was really good and we're delighted with the three points."
Praise was quick to pour in for Reina's performance, with a number of team-mates highlighting the fact that he became the first Spanish player to play in all four of major European leagues (Germany, Spain, England and Italy). Continue reading below for a selection of the best social media reaction to Reina's first game for Bayern, as well as to discover what did on his day off...
Neuer heads to the mountains
Neuer, meanwhile, donned his skis to make the most of a rare weekend off. The 28-year-old posted the following picture on Instagram alongside the caption:
"Great performance by the team yesterday. That means we can relax and enjoy the rest of the weekend. Have a nice Sunday!"
A photo posted by @manuelneuer on Mar 15, 2015 at 5:10am PDT