Analyzing the components of Tuesday's trade that sent Ugueth Urbina to Boston:

To the Red Sox:

Ugueth Urbina, RHP
Ugueth Urbina(Allsport)	What's to gain: A hard-throwing closer to solidify the Red Sox bullpen. Urbina saved six of seven chances after his trade to the Yankees fell apart in mid-June. He saved three games in as many days and pitched five consecutive days a couple weeks ago. He's still a power thrower with his fastball and slider. He's only 27.
	What's to lose: Urbina, once his arm blows. One scout told the Sporting News that his mechanics are awful and that he hasn't changed his throwing motion, which will probably lead to the same arm problems that caused two surgeries last year.
	What's his role: Urbina will likely inherit the majority of closing work in Boston. His margin of error, however, will be small with Derek Lowe and Rod Beck still in the bullpen.

To the Expos:

Tomo Ohka, RHP
Tomo Ohka(Allsport)	What's to gain: A 25-year-old offspeed pitcher who became a Red Sox minor-league legend by going 15-0 two years ago and throwing a perfect game last year. His fastball only reaches 90 mph but it has nice late movement. His split-finger and changeup are deceptive.
	What's to lose: Ohka foundered in his major-league starts this year after showing promise down the stretch last year. When his stuff isn't sharp, he gets pounded. He could use another pitch in his arsenal, even if it's more breaking stuff.
	What's his role: Ohka will slide into Montreal's rebuilt rotation. Here's hoping the stability of regular starts helps him out.