Aside from the World Cup, the European championship is the most competitive tournament in the world. The tournament features some of the globe's best players, and the upcoming 2016 competition in France will serve as an indicator of which teams are poised to excel at the 2018 World Cup.
The current crop of 53 eligible teams is split into nine groups, with the group winners, runners-up and the best third-placed team earning a tournament berth. The eight remaining third-placed teams face off in a playoff to determine the last four teams to join the host nation in the 24-team field. While this week marks the halfway point in the qualification process for most nations, there are some teams that already stand out for either playing above or below their expected standard.
Here is a look at three Euro 2016 contenders that are showing signs of vulnerability and could be in danger of not qualifying, along with three overachieving teams that could be dangerous sleepers to not only earn a berth to the tournament but make waves at the Euros.
Belgium | Qualifying record: 1-0-2 (win-loss-draw) | Group rank: 4th
Snapshot: Belgium, which is fourth in Group B, will battle Bosnia-Herzegovina, Wales and Israel for the top spots.
Belgium started strong with a 6-0 opening win over Andorra but subsequent draws against Bosnia-Herzegovina and Wales have raised questions about how the team uses its attacking resources. ...
Mousa Dembele has hinted he could leave Tottenham this summer, saying that his lack of games at under Mauricio Pochettino has been "very disappointing."
Dembele, 27, has played 21 Premier League games for Spurs this season, but has only started nine of those and has completed just two full matches.
Pochettino's faith in young central midfield pairing Ryan Mason and Nabil Bentaleb has seen Dembele struggle for chances, and the Belgium international says he will review his situation at the end of...
Everton striker Romelu Lukaku has been ruled out of Belgium's forthcoming Euro 2016 qualifiers through injury.
The 21-year-old limped off in Sunday's 2-1 win at QPR with a hamstring problem which manager Roberto Martinez hoped would prove just to be cramp.
However, the Belgian Football Association has announced Lukaku and Anderlecht midfielder Steven Defour will not feature against Cyprus on Saturday or Israel the following Tuesday.