World middleweight champion Sergio Martinez believes his most realistic chance of winning recognition as the world's best boxer lies in a bout with Floyd Mayweather Jr.The 36-year-old Argentine (48-2-2 ),named 2010 Fighter of the Year by the Boxing Writers Association,said that Manny Pacquiano was relutant to take him on.He accused the Filipino of making unrealistic weight demands and said he was targeting the undefeated Mayweather instead.