Art Garfunkel has had some vocal problems the couple of years. Whether or not that led to Paul Simon deciding to tour with Sting is unknown, but here is Sting, singing The Boxer with Paul. Does he do it justice? You decide.
photo By Yancho Sabev (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons