I can't find it, but I saw an Whoscored tweet about him, saying that he has the worst save percentage in the Bundesliga the last 3 years, or something like that.
He may well have, but it depends how you look at it. He played in two games last year, one of which was as a sub in the 87th minute during the final game of the season; the other was a home game to Dortmund in March that Augsburg lost 3-1. He played in nine in 2014/15 and 13 in 2013/14.
2013/14 - 13 Games - 33 Saves/54 Shots on Goal - 61.1%
2014/15 - 9 Games - 29 Saves/ 44 Shots on Goal - 65.9%
2015/16 - 2 Games - 2 Saves/5 Shots on Goal - 40%
That is a total of 24 Games with 64 Saves/103 Shots on Goal - 62.1%.
Timo Hildebrand's numbers over a similar period for Eintracht Frankfurt in 2014/15 and Schalke in 2013/14
2013/14 - 12 Games - 40 Saves/64 Shots on Goal - 62.5%
2014-15 - 3 Games - 10 Saves/18 Shots on Goal - 55.5%
Total - 15 Games - 50 Saves/82 Shots on Goal - 60.9%
Werder Bremen's Raphael Wolf
2015/16 - 0 Games
2014/15 - 27 Games - 71 Saves/121 Shots on Goal - 58.6%
2013/14 - 21 Games - 76 Saves/117 Shots on Goal - 64.9%
Total - 48 Games - 147 Saves/238 Shots on Goal - 61.7%
And for good measure another older keeper: Dortmund's Roman Weidenfeller
2015/16 - 1 Game - 1 Save/1 Shot on Goal - 100%
2014/15 - 25 Games - 53 Saves/84 Shots on Goal - 63.0%
2013/14 - 30 Games - 71 Saves/103 Shots on Goal - 68.9%
Total 56 Games - 125 Saves/188 Shots on Goal - 66.4%
He's a 39 year old third choice keeper here. He'll hardly play any games. At Augsburg, he added depth to a plucky team that finished 8th, 5th and 12th, despite having never reached the Bundesliga prior to their initial promotion in 2011/12. He'll be adding depth and valuable experience off the pitch, which is likely more important than what his save percentage was.