1. How tall is too tall?

Four weeks into the season and clubs are still working how best to fit as many talls as possible into the side without affecting team balance. Despite the emergence of Tom Bellchambers as a quality ruckman this year, Essendon coach James Hird still openly wants erstwhile no.1 ruckman David Hille back in the side, preferably on Monday against Collingwood. How will Bellchambers, Hille and Paddy Ryder go in the same team?

Clubs are still trying to establish what is the best mix of talls. Is it two traditional ruckmen and a tall forward as the Bombers are contemplating? Or is it the Collingwood model of one traditional-type ruckman (Darren Jolly) and two power forwards who give Jolly a hit-out as required - Leigh Brown and Chris Dawes?

Geelong will try to load up with as many talls as it can carry at the MCG on Tuesday in an attempt to catch out the undersized Hawthorn backline. It worked a treat last year in round two when Brad Ottens pushed forward to take a number of grabs, but if he plays forward this time around with James Podsiadly and Cam Mooney as well, who plays in the ruck?

2. Yes, North Melbourne is still in the competition.

With two games in Perth and a bye in their first four weeks of the season, North Melbourne has barely been a blip on the radar of season 2011. The Roos sit winless and ahead of only Gold Coast on the ladder. They host another winless side - Richmond - at Etihad Stadium late on Sunday and this much is clear: the loser won't be playing finals footy this year.

3. How good are the Hawks?

There has been a bit of noise out of Geelong about Tuesday's clash with Hawthorn. Paul Chapman has said that the players have vowed never to lose to the Hawks again after the monumental upset that was the 2008 Grand Final, and with four wins since (albeit by a combined margin of 20 points), they are living up to the vow. The Cats have better form than Hawthorn so far this year, what with away wins at Fremantle and Sydney, yet they can't surpass the Hawks as second favourite for the flag. It should be a corker.

4. Big game at Etihad

Plenty riding on the game at Etihad on Saturday night. The Crows have been poor since the opening round win over Hawthorn, dropping games to Fremantle and Port Adelaide. Injuries are depleting the side again and this week marks just their first game outside South Australia. Meanwhile, many believe poor coaching from the Blues contributed to the drawn result against the Bombers last weekend. The pressure valve will rise just that bit more if the Blues can't eke out a win here.