Proteas keeper De Kock to be assessed before fourth test

CAPE TOWN, (Reuters) - Wicketkeeper Quinton de Kock will have a final assessment on his troublesome knee on Wednesday ahead of the fourth test against England in Pretoria, Cricket South Africa said. De Kock was injured while walking his dog on the eve of the third match at the Wanderers and replaced in the side by Dane Vilas. Opener Stiaan Van Zyl’s dismal series is over after he was released from the squad with uncapped Stephen Cook set to replace him at the top of the order in the match which starts on Friday. Van Zyl, usually a middle-order batsman, scored just 69 runs in five innings at an average of 13.80. Fast bowler Dale Steyn has already been ruled out as the Proteas seek to give him more time to recover from a shoulder injury ahead of the five-match one-day international series starting on Feb. 3. England have won the test series after taking an unassailable 2-0 lead ahead of the final match at Centurion Park. (Reporting by Nick Said, editing by Ed Osmond; nick.said@thomsonreuters.com; +27832722948; Reuters Messaging: Reuters Messaging: nick.said.thomsonreuters.com@reuters.net)