The Copa America's knockout stage will begin Wednesday but unfortunately, it has been more notable for what has ­happened off the pitch rather than on. The most controversial is the suspension of Brazil's Neymar for four games which rules him out of the entire tournament. Hosts Chile also saw star midfielder Arturo Vidal arrested for drunk driving last week.The loss of Neymar leaves the tournament lacking serious star power, especially with Uruguay's Luis Suarez still serving an international soccer ban. Neymar's suspension arose out of confusing circumstances. He was originally suspended for receiving yellow and red cards for an on-field confrontation in the game against Colombia. This was supposedly for one game, but then increased to four, after the game's referee said ­Neymar had waited in the tunnel after the game and verbally abused him.

This is bad and the Brazilian captain should have known better. However, it was an indication of the rough stuff on the pitch as Neymar was repeatedly fouled. One wonders if the last competitive meeting between the two countries in last year's World Cup played a part. That game, a quarterfinal, was filled with fouls, mostly from Brazil, until Neymar suffered a back injury inflicted by a Colombian player jumping onto him.

While Brazil won their next Copa game against lowly Venezuela to reach the first knockout stage, they will need to work harder, ­especially to avoid any repeat of last year's World Cup when after losing ­Neymar, they were subsequently blown out by Germany.

The loss of Neymar improves ­Argentina's chances, who will be ­eager to win their first Copa America title since 1993. Lionel Messi and Argentina have not exactly impressed so far, drawing with Paraguay and gaining 1-0 wins over Uruguay and Jamaica. For all the overwhelming success Messi has with Barcelona, he does not have anywhere near the same effect with Argentina, even with the likes of Sergio Aguero and Angel di Maria alongside him.

Argentina will go up against Colombia, themselves a talented team with stars like James Rodriguez and Radamel Falcao, and if the Argentines win, they could find themselves in a mouthwatering quarterfinal clash with Brazil.

Chile overcame the arrest of Vidal, who was later released, to beat ­Bolivia 5-0 and advance against Uruguay. ­Besides being the host, Chile have ­extra motivation in having never won the Copa America.

Here's hoping the knockout stages of the Copa American will deliver a lot more drama and action on the field.

The author is a Beijing-based freelance writer. hcpyip@gmail.com