For the third consecutive year, the year-end No. 1 is still up for grabs going into the Masters Cup. Lleyton Hewitt holds the No. 1 spot -- but he still has the potential to give it up to Andre Agassi. For that to happen, Agassi would have to have an outstanding week and Hewitt can't reach the final (it's complicated -- Greg Garber breaks it down here).

	Mal-Adjusted
	Washington Former ATP Tour pro MaliVai Washington is providing ESPN.com with in-depth analysis during the Masters Cup. Washington, a tennis analyst for ESPN, reached the 1996 Wimbledon final.

With that said, on paper the two groups in the round robin played out in Agassi's favor. Agassi has never lost to two of the people in his group. He is 3-0 against Roger Federer and 4-0 against Jiri Novak, who he plays on Wednesday (ESPN2, 6 a.m. ET). On the other hand, Hewitt has losing records against two of the players in his group. He's 2-4 against Carlos Moya and 3-4 against Marat Safin. So, it was very important for Hewitt to get his first match under his belt Tuesday against Albert Costa.

In another big race, Safin has the opportunity to overtake Agassi for the No. 2 spot, but he did himself a huge disservice by losing in the opening match to Moya -- a man he beat just two weeks ago.

A guy who looked tremendous in his opener against Juan Carlos Ferrero -- in his first appearance in the year-end championships -- was Federer. Coming into this, people weren't talking about Federer as a potential champion. If he can get past Agassi in the gold group, don't be surprised to see him in the final because he should beat Novak, the other player in his group.

As for French Open champion Costa, I think he's very happy to have qualified for Shanghai. He says he's still living a dream. I suspect that he won't get past the round robin.

In the red group, I see Hewitt getting through and a toss-up between Moya and Safin getting to the semifinals. Safin can't afford to lose any more matches this week if he has any hopes of overtaking Agassi for the No. 2 spot.

Barring some strange happenings, Hewitt should finish the year as No. 1 for the second consecutive season. The last person to do that was Pete Sampras, whose six-year run ended in 1999.