Ronald Ssemanda took two wickets in the final over to help Uganda beat Hong Kong by one run in a thriller in Buenos Aires. The victory puts them on par - in terms of wins and points - with Afghanistan and Papua New Guinea.

Hong Kong got off to the worst possible start chasing 181, losing two wickets - both to fast bowler Kenneth Kamyuka, who took 4 for 21 - without a run on the board. However, Manoj Cheruparambil and Hussain Butt scored half-centuries to lead the recovery with an 84-run stand. Hong Kong looked comfortably placed at 124 for 3 but a collapse ensued as they lost their next four wickets for 49 runs, including Butt. Zain Abbas, the No.5 batsman, resisted throughout the ordeal with a determined 35 before Ssemanda accounted for him and wicketkeeper James Atkinson in the 50th over.

Kamyuka had earlier contributed 37 after Uganda had failed to consolidate the 64-run opening partnership between Roger Mukasa - who top-scored with 67 - and Arthur Kyobe. Munir Dar, the left-arm spinner, took 4 for 30 and triggered a middle-order collapse, in which Uganda lost five wickets for 59 runs.

In the context of the match, Kamyuka's cameo towards the end proved decisive. He paid tribute to his coach Ebrahim Mohamed: "The coach has helped us with these situations by working on the mental side of our game. He has told us we should be soldiers and fight to the last ball. I enjoy bowling when there is a lot of pressure on the batsmen."

Mohamed said he was confident his team could pull off a win despite Hong Kong being in control for much of their innings. "I didn't give up hope as we have been in these type of situations before and from the moment we got a couple of late wickets, there was always a chance and we were determined to fight until the last ball."

Afghanistan completed a comprehensive eight-wicket win over Papua New Guinea at the Hurlingham Club Ground, to top the table as a result of three wins and an impressive net run-rate. Hamid Hassan, the right-arm medium bowler, took 3 for 26 and the other Afghanistan bowlers chipped in with at least a wicket each as PNG struggled from the outset, eventually managing just 93. Vani Morea, the PNG opener, fell for a duck to medium pacer Daulat Ahmadzai, who took 2 for 27, and his team never recovered from the early loss. PNG were bowled out in just 31 overs, with Jamie Brazier top-scoring with 22, and managed a highest partnership of just 29 for the fifth wicket.

In reply, Afghanistan's openers provided them the ideal start with wicketkeeper and stand-in captain Karim Sadiq following up his six catches in the PNG innings with a half-century, and adding 63 with Shafiqullah. "I am very proud that I captained my country, took six catches and scored a 50. I am also pleased we have helped our net run-rate and hopefully we go out and win on Friday," Karim said. He was confident ahead of his team's next match against Cayman Islands and was determined to qualify for the 2011 World Cup. "We beat Cayman Islands in a practice match before this tournament and we have our captain coming back for this match so I am hopeful that we can win.

"It is my dream to get my very poor country to the World Cup. All of our people want to watch our country play in the tournament and watch the games live on television."

The PNG captain Rarva Dikana singled out the batting as the major worry and hoped for an improved performance in their next match against Hong Kong. "We need to work hard on our batting and if we put on a good score we should be able to defend it given our bowling strength. We have been quietly confident throughout and hopefully we will do well on Friday."

Afghanistan's next opponents, Cayman Islands, also registered a comfortable six-wicket win over hosts Argentina - who are now relegated to Division 4 - to take the No.6 spot on the points table, though the game was not as one-sided. Argentina squandered an encouraging start by opener Lucas Paterlini, who scored a quickfire 70 off just 50 balls, to be bowled out for 165. The opening pair added 40, but the Cayman Islands bowlers then triggered a collapse where the hosts lost 7 for 72, with only two batsmen in the top seven getting to double figures. Pablo Ferguson and Estaban Macdermott, the Argentina captain, added 35 for the eighth wicket but, despite their resistance, the Cayman Islands bowlers, led by offspinners Alessandro Morris and Saeed Mohamed - who took 5 for 34 between them - ensured a quick conclusion to the Argentina innings.

The Cayman Islands' response started off soundly, with openers Ainsley Hall and Ramon Sealy - who remained unbeaten on 66 - added 64. They then lost two quick wickets, but Sealy added a further 61 with captain Steve Gordon to put the game firmly in his team's grasp.

Macdermott was disappointed at his team's relegation: "We will have to adapt and face up to the situation we are in and we will look to get promotion from Division 4. The tournament is not over yet and we owe it to the people who come to watch our matches and we owe it to ourselves to do our best in our last two games."

Sealy, the star for Cayman Islands, was satisfied after his team registered its first win in the tournament. "It's good to get a win at this event. We were always confident of reaching the target as it wasn't that big a total but it was nice to get a victory."