In 2007, Kallis scored five centuries in four Tests, making him just the fourth man after Bradman, Ken Barrington and Matthew Hayden to score four centuries in four Tests on two different occasions. Regardless of style, Kallis has a remarkable batting average in the mid-50s, and is rated as one of the best batsmen in the world. Although still a very capable bowler with over 275 Test wickets, he impressed mostly with the bat between 2005 and 2007. As a result, he evolved into more of a batting all-rounder, a role in which he continued because of the emergence of Dale Steyn, Morné Morkel, and Paul Harris. Kallis is the only man to score over 13,000 runs and to take over 290 wickets in Test cricket. Sir Garfield Sobers managed over 8,000 runs and 200 wickets by comparison, at very similar averages.