Previewing the 2017-18 UEFA Champions League

Cristiano Ronaldo and Real Madrid will try to make history with a third straight title, but ESPN's SPI favours Barcelona. Kirsty Wigglesworth/AP Photo

The UEFA Champions League season formally begins this week, as the group stage commences across Europe on Tuesday.

Last season, Real Madrid won its record 12th European Cup and became the first team to win successive titles in the Champions League era (since 1992-93). Now Real Madrid look to become the first team to win three straight European Cups since Bayern Munich did so from 1974 to 1976.

Real Madrid is currently the betting favourite to lift the trophy, followed by PSG, Bayern Munich and Barcelona. ESPN's Soccer Power Index favours Barcelona at 20 percent, with Bayern (17 percent) and Real Madrid (14 percent) next in line.

Bayern and PSG were drawn together in Group B, and the first of their two group meetings will be on Sept. 27 in Paris. This is the fourth time they've been grouped together in Champions League play, and the first since 2000. PSG has won all three previous home meetings; Bayern has two wins and a loss at home.

PSG hope Neymar can push the team at least to its first semifinals since 1995. PSG is one of five clubs to reach the knockout stage in each of the previous five seasons, along with Arsenal, Barcelona, Bayern and Real Madrid. But the French champion went out in the round of 16 last season and in the quarterfinals the previous four seasons.

With Manchester United winning the Europa League last season, England is now the second country to put five teams in the Champions League group stage, joining Spain in the 2015-16 season. For the first time since 1997, Arsenal did not qualify for the group stage, ending the second-longest streak of appearances at 19 seasons (Real Madrid is at 21).

On the individual level, Cristiano Ronaldo will have the opportunity to add to his UCL-record 105 goals. Lionel Messi is six shy of being the second player to reach the century mark in Champions League play. Real Madrid's Karim Benzema can also climb the scoring charts this season; his 51 goals are fifth-most all time, and he's five away from tying Ruud van Nistelrooy for fourth.