Mumbai, Oct 21 : England pacer Reece Topley walked off the ground midway through his fourth over with an injury to the index finger on his left hand during the match against South Africa in the Men's ICC ODI World Cup at the Wankhede Stadium here on Saturday. Topley tried to evade the ball when Rossie Van Der Dussen played a back-foot punch to a back-of-the-length delivery for a boundary on the fourth ball of the over. The England pacer was not fast enough and the ball seems to have hit the edge of the finger, around the nail. The England team physio came out to check on Topley's finger and the bowler bowled the next delivery, which too was dispatched to the boundary. Topley soon signalled to skipper Jos Buttler that he was not feeling right and walked off the ground. Former England captain Joe Root bowled the last ball of the over. Topley had given England the early breakthrough when he got Quinton De Kock when he got a decision reviewed and turned in their favour after Ultra Edge showed a spike as the ball went past the bat. It was pitched a bid wide and swung further away and de Kock played a cover drive only to nick it back. The wicket came on the second ball of the opening over after de Kock had despatched a gentle loosener for a boundary. South Africa recovered from the setback and reached 59/1 at the end of the mandatory Power-play. Reeza Hendricks and Rassie van der Dussen played cautiously before opening up in the last four overs of the Power-play, hitting 47 runs. /IANS