After the Miami Dolphins found pass rusher Cameron Wake in Canada and the Indianapolis Colts did the same with linebacker Jerrell Freeman, teams now are looking closely at former USC and Toronto Argonauts standout defensive tackle Armond Armstead, according to sources.

Armond Armstead played three seasons with the Trojans (2008-10), starting 17 games and recording 59 tackles. Craig Bennett/Icon SMI

Last week, Armstead visited with the New England Patriots, Philadelphia Eagles and Colts, and might make more visits this week before making a decision about where to sign, which is expected to take place this week.

In the 6-foot-5, 300-pound Armstead, an NFL team will be getting the equivalent of a high draft pick months before the April draft.

The 22-year-old former USC standout went to Canada to prove he was healthy enough to play football again after suffering a heart attack, the subject of a lawsuit against the school in which Armstead alleges the attack was brought on by painkillers.

Armstead played three seasons for USC (2008-10), starting 17 games and recording 59 tackles. He did not suit up for the Trojans in 2011 because he was not medically cleared for competition and then went undrafted in the 2012 NFL draft.

Playing for Toronto this season, Armstead had six sacks and helped the Argonauts win the Grey Cup. Toronto released him earlier this month, reportedly so he could pursue a spot in the NFL.

Wake has 43 sacks since signing with Miami before the 2009 season, including 15 this season. Freeman had 145 tackles, two sacks and an interception in his rookie season with the Colts in 2012.

Information from ESPNLosAngeles.com's Pedro Moura was used in this report.