VERNON KAY: San Francisco's offensive weapons make Colin Kaepernick a big threat, but Jay Cutler lacks the leadership to be one of the best quarterbacks in the NFL.

• Chicago Bears visit the San Francisco 49ers in Sunday late game
• San Francisco won their opening game of the season at Dallas Cowboys
• Chicago beaten by Buffalo Bills 23-20 at Soldier Field during week one
• Jay Cutler has to show more leadership to be one of the best quarterbacks
• Colin Kaepernick's dual threat causes defenses all kinds of problems
• The 49ers defense is in transition, but Justin Smith is amazing 

It is always difficult for a team in the NFL to start positively when they’ve got a new head coach. The Chicago Bears, since losing Lovie Smith, have had a massive transition. Last year was a difficult year because of people’s thoughts towards Jay Cutler. I think he’s the key to this team and it’s about how consistent he can be and whether he has got the weapons to be successful.

I like Cutler but, from an outside perspective, I think he needs that extra level of leadership - something like an Aaron Rodgers or Tom Brady gives a team. If you look at Peyton Manning, he is the leader of the Denver Broncos, and once you’ve got a quarterback who can establish leadership then it makes it easier for the offense. I don’t think Cutler has that presence or persona. He can throw the ball, but if he wants to be a dominant force then he needs to be a bigger leader.

                                            Vernon Davis catches a touchdown pass during the San Francisco 49ers' 28-27 win over Dallas Cowboys

                                                                 Colin Kaepernick, pictured handing off to Frank Gore, provides a threat with both his arm and legs

If you look at the 49ers, in my eyes Colin Kaepernick is not the best quarterback in the league. But San Francisco have given him probably the best set of options.

He has got good receivers in Anquan Boldin and Michael Crabtree – regardless of what Richard Sherman says. He’s also got a decent tight end in Vernon Davis and a good running game led by Frank Gore.

Also, with Kaepernick’s ability to run the ball as well, the defense has to draw up another play in the book to stop that. Not all quarterbacks like to move outside the pocket and run the ball.

                                            The Chicago Bears suffered a 23-20 defeat by the Buffalo Bills in their opening game of the season

                                            Jay Cutler came under fire last season but has retained his place as the starting quarterback for the Bears

If the Bears are playing the New England Patriots and Brady, it will be a completely different game. All the defense has to do is make sure they are where they need to be to catch the ball. But with the 49ers, not only have they got to be wary of the running game and the passing game, they’ve also got to realise that they have to contain Kaepernick because he is a weapon.

In the San Francisco defense, Justin Smith is awesome – I wish he played for the London Warriors. I can’t believe how powerful he is. I watched the game against the Cowboys on Sunday and he is just something else. With the Cowboys, three of their last four first-round draft picks have all been offensive linemen, so we are not talking about dodgy offensive linemen. But Smith literally ripped them apart and is quite a dominant force.

It’s difficult in transition and the 49ers have a couple of rookies in their defense. Rumour has it that Jim Harbaugh has lost the locker room, but when you have the reputation that the 49ers have, it is hard to let go of. They have still got Patrick Willis in there who is an amazing linebacker and can lead the troops as well. I have no doubt that San Francisco will make the play-offs.

                                            San Francisco 49ers defensive lineman Justin Smith sacks Dallas Cowboys quarterback Tony Romo

I thought the Bears where unlucky to lose to Buffalo in week one. But the thing with week one is that a lot of teams hold things back in pre-season and don’t show their hand.

If you look at the way the Detroit Lions came out on Monday against the New York Giants, they were just phenomenal. They have got a new offense in store and their offensive coordinator Joe Lombardi used to be the quarterback coach for the New Orleans Saints. They are literally running the Saints offense and it works for the artillery that the Lions have.

Obviously, with Calvin ‘Megatron’ Johnson, you can just throw the ball anywhere and he will go and get it, but they’ve got Reggie Bush to run the ball and they’ve got numerous tight ends that they’ve brought in to mirror the Saints offense. It works for their quarterback Matthew Stafford and he had a great game. They just destroyed the Giants defense on Monday. 

Calvin Johnson celebrates a touchdown during the Detroit Lions' thumping win over the New York Giants

On the flip side, Eli Manning has won the Super Bowl twice with the Giants. But, if you talk about offensive weapons, slowly over the last couple of seasons they have taken away the team around him. He’s playing with a handful of rookie running backs and has got a new set of receivers. He has got a completely new offense and he struggled.

I think the Bears will have it tough in their division. That NFC North is the toughest division in the league with the Lions, Packers and Vikings. It is ridiculous.

Now that the Vikings have settled on a quarterback and are taking the ball away from Adrian Peterson, that they have got confidence in the troops they’ve got around Matt Cassel. They’ve given Cassel confidence and let him play his game instead of undermining him by giving the ball to Peterson all the time. Now they’re willing to throw the ball, it makes defenses think: ‘Adrian might not get the ball, so we’ll have to go cover two instead of cover four.’ 

                                            San Francisco will play their first competitive game at their brand new Levi's Stadium in Santa Clara

Sunday night’s game will be the first at San Francisco’s brand new Levi’s Stadium. I’ve not been yet - I’ll probably be there for Super Bowl 50 - but by all accounts it is absolutely stunning. I have a friend who has been there who said it is amazing.

I just hope it starts to build a reputation like Candlestick Park did because I remember watching American football late at night during the 1980s on Channel 4. They were those muddy games where the 49ers were playing the Giants or the Cowboys. Old school fans will miss those muddy shirts in the play-offs.