Ignorance is bliss—at least it was until I had to take a short test on concussions for my US Soccer coaching license last year.

Until that point, I was somewhat aware of but not that focused on the dangers players face from concussions.

"From a physician’s standpoint, concussion is when physical trauma causes the brain to malfunction," said Howard Kerpen, Lorber professor of medical education at the Hofstra North Shore-LIJ School of Medicine in New York.

Problem is, there's no obvious physical evidence for this that can be detected through standard CAT scan or other tests.

"The individual involved can have many non-specific symptoms such as confusion, nausea, dizziness and irritability," Kerpen told Fox News Latino.

He says parents should take immediate action. "My response would be to have my child seen by a physician as soon as possible, preferably one with experience in trauma."

There are as many as 10,000 trips to the emergency room for soccer concussions each year, reports say. Most aren’t immediately life threatening, but any concussion can lead to greater problems later in life.

While US Soccer appears to be taking some measures at the youth level, some medical professionals feel it's time for us to step up the game.

Parents who fled the football gridiron for fear of concussions will likely do the same with soccer unless courageous decisions are made.

One factor that might force the needed changes, if they're not put into place voluntarily, is a class-action suit brought by parents and players in California.

In the suit, they claim that FIFA and several U.S. soccer organizations have been negligent in the treatment of head injuries.

The suit seeks no monetary damages, and it claims that, among other things, limits must be put on how many times players under 17 are allowed to head the ball.

The judge has yet to decide whether the case will be heard.

Banning or limiting heading in youth soccer would seem a logical solution since the brain of a youngster is more likely to be harmed than that of an adult – but adults are also at risk.

A study published last year in the journal, Radiology, came to some alarming conclusions about the effects of adults of heading the ball.

“Soccer players who ‘head’ the ball with high frequency demonstrate poorer performance on memory tests and have brain abnormalities similar to those found in traumatic brain injury patients," according to the research, which was led by Michael Lipton, medical director of MRI at Montefiore Medical Center in New York.

Participating in the study were 37 amateur adult players with a median age of 31. They had been playing for an average of 22 years, including an average of ten months during in the previous year.

Lipton and his fellow researchers said further research should be a priority, but recommended that, as an interim measure aimed at preventing brain injuries, players should control the amount of heading they do.

Soccer chiefs at all levels would be wise to avoid the increasingly expensive lawsuits that are expected to cost the NFL billions of dollars, and act to reduce the incidence of concussions – at least where youth soccer is involved.

Since taking that concussion course, heading has not part of the practices I run for my team of under-9 boys.

Now, I don't accuse them of being cowards if they step back and let the ball bounce during a game, or if they try to control it with another part of the body.

Indeed, I encourage it.

Note: On Wednesday, May 7, two days after the publication of this column, District Court Judge Phyllis Hamilton in Oakland, California, ruled that the complaint mentioned above against FIFA and five U.S. soccer organizing bodies was full of “inconsistencies, contradictions and a lack of clarity.” Lawyers for the group of parents who brought the suit may be able to amend the complaint.

Video of the week

What a goal! South African up-and-coming star Menzi Masuku of Orlando Pirates FC scored this stunner as part of a brace he got against South African league rival, SuperSport United, last week in Johannesburg.

From the wires

Pep Guardiola is headed home to visit Lionel Messi and his Barcelona teammates in the Champions League semifinals.

The current Bayern Munich coach, who led Barcelona to 14 titles before heading to Germany and helped win more as a player, will face his old team in the first leg on Wednesday at Camp Nou.

Guardiola has already won the Bundesliga title this season and will next meet his childhood club and former teammate Luis Enrique.

Messi and Luis Enrique, who calls Guardiola his "friend," both said Tuesday that the chance of reaching a European final was a greater motivation that facing the man already considered a club great.

"With Guardiola, besides the titles, which are the most important thing, I grew and learned a lot as a player," Messi said. "He knows us, and we know what he wants and asks of his team. It's 50-50, we all know each other very well."

No other coach besides former Real Madrid nemesis Jose Mourinho has left his mark on European soccer like Guardiola, who perfected Barcelona's passing style and implanted it at Bayern.

The possession-based approach has often worked, but when it hasn't led to titles it has earned Guardiola the criticism of being more interested with having the ball than putting it in the net.

The arrival of Luis Enrique to coach Barcelona, and, equally important, that of Luis Suárez to provide a traditional striker up front, has let Barcelona finally vary its tactics, which had atrophied since Guardiola left. Barcelona can now win through set pieces and long balls for Suárez, something rarely seen over the past decade at Camp Nou.

Barcelona and Bayern lead the four teams left in the competition in passing, with an eerily equal completion rate of 91 percent. Barcelona has made 6,308 total passes compared to 6,230 for Bayern. Real Madrid is a distant third with 5,183.

"I don't think Pep has any doubts about what we will do," Luis Enrique said. "He knows the players, and he knows me as a coach because I was with the "B'' team when he was here.

"It will depend on who is more precise and responds better to given situations. We are both teams that need the ball to attack and defend. I think this will be one of the most attractive matches to see in Europe."

The Associated Press contributed to this report.