Looking back on three things discussed here before the San Francisco 49ers' 2013 exhibition opener, a 10-6 defeat to the Denver Broncos at Candlestick Park: 1. Young receivers. The 49ers would like 2012 first-round pick A.J. Jenkins to seize the starting job opposite Anquan Boldin. Jenkins did not make a strong positive statement in this game. "Uh, could have been better," coach Jim Harbaugh said afterward. Jenkins lost a fumble following his lone reception.