data-mm-id=”_g0mvhyrga”>Three weeks of fantasy football are in the books already. Man, how time flies. Fortunately, this week was not the injury bloodbath that Week 3 was, as no big-name fantasy stars went down on Thursday, Sunday, or Monday. Still! A good fantasy player never lets a waiver wire opportunity pass, if only to prevent others from benefitting. Here are the best fantasy football waiver wire pickups for Week 4. (All stats via ESPN PPR leagues)Justin Jefferson / Adam Bettcher/Getty ImagesJustin Jefferson, WR, Minnesota Vikings (Available in 62 Percent of ESPN Leagues)Jefferson was the Vikings' first-round pick this year, and it took a few weeks for him to get acclimated. Sunday seems to indicate he's done just that, as he put up Randy Moss-like numbers in the first …