Root, Denly and Sibley hit half-centuries as England begin South Africa tour

• England rack up 309 for seven against Invitational XI
• Root top-scores with 72, while Burns and Buttler fall cheaplyJoe Root, Joe Denly and Dom Sibley all banked unbeaten half-centuries as England got their tour of South Africa under way with a leisurely day at the crease in Benoni.Lining up against a willing but limited Invitational XI at Willowmoore Park on the first day of two, England racked up 309 for seven, with all three of their top scorers retiring out to give others a chan