John Terry looks set to miss England's World Cup qualifier against Kazakhstan at Wembley on Saturday with a back injury. Terry suffered the problem in Chelsea's Champions League tie against CFR Cluj last week and played with a protective pad in his club's win over Aston Villa last weekend. The England captain was in pain after that match and was forced to pull out of a training session with Fabio Capello's squad early on Wednesday. The FA released a statement on Thursday confirming that Terry's back complaint had prevented him from training again and he is almost certain to be sidelined for the Kazakhstan clash, as well as the trip to Belarus next week. Matthew Upson is expected to deputise for Terry, while Rio Ferdinand will take the captain's armband. While Terry battles with injury, England striker Wayne Rooney believes he has shaken off a surprising early-season slump. Rooney has scored in his last three games for Manchester United, in addition to the goal he got in the 4-1 World Cup win over Croatia in Zagreb last month. But his hot streak was much needed after a sluggish start to the campaign, which saw him left out of Sir Alex Ferguson's side against Bolton. The 22-year-old concedes he was below-par in the opening weeks because he was trying to do too much for the team. Spain stays at No. 1 European champion Spain extended its lead as the world's No. 1 football nation in the latest FIFA rankings published Wednesday. Italy and Germany remain second- and third-ranked. Brazil is South America's best, climbing two places to No. 4 overall, while pushing the Netherlands and Croatia down a place each. Argentina remains ranked seventh. The one change in the top 10 nations has Russia returning at No. 9 at the expense of fellow Euro 2008 semifinalist Turkey, which drops three places to No. 13. The two traded places in the elite group last month. Cameroon continues to rise as the leading African nation, climbing two places to No. 12, two places above England. The United States is once more best among CONCACAF countries, climbing seven places to No. 21, while Mexico holds steady at No.24. Japan leads the Asian Confederation at No. 32, while New Zealand is the big mover at No. 54. Its two World Cup qualifying match wins over Oceania rival New Caledonia helped lift the Kiwis up 57 places. Other nations rising to best-ever placings were Lithuania, up 17 places to No. 37, and Macedonia, up 10 to No. 46 after beating Scotland in a World Cup qualifier. The Scots suffered the biggest drop in status among leading nations, down 10 places to No. 26. A total of 125 internationals played in the past month counted toward the rankings.