The pair sustained injuries in the Lions' taxing 15-point win in the wet over Fremantle last weekend.
While Bradshaw has a minor hamstring tear which will see him out of action for two or three matches, Brennan is a chance to play against North Melbourne on Saturday night.
Coach Michael Voss said Lachlan Henderson will most likely fill in for Bradshaw up forward, while Tim Notting will step up to take on the back up ruck duties behind Mitch Clark, should Brennan fail to prove his fitness in time for the round 17 clash.
Voss will not be tempted to rest any players despite gruelling wins against Geelong and Fremantle in the last fortnight. Instead, the players will have a light week with a focus on recovery, skills and intensity.
“We’re certainly not in the scope of being able to rest players,” Voss said.
“We’re not three games clear at the top of the table, so for us, it’s about being able to maintain that form and that toughness and that durability to be able to last out a season.”
That includes not giving rookie midfielder Daniel Rich a break.
The 19-year-old has played every game in his debut year, and was best on ground against Fremantle with 31 disposals and a whopping 12 centre clearances, a quarter of the Lions total.
While the Lions were outdone by Fremantle in kicks (180-174), handballs (156-151) and marks (64-54), the visiting side dominated the inside 50 count (62-34) while enjoying greater efficiency with the ball.
“We’d like to think that we can transition the ball from one end of the field to the other end and not overpossess it,” Voss said.
“We don’t handle the ball 400-plus times, but our efficiency is right up there. We have something like 25.6 possessions per goal, which is more the relevant stat now than the actual total possessions, I think.”
While the Lions have now recorded 10 wins for the season, Voss knows his side is likely to need two more to guarantee a place in the final eight.
“That’s (12 wins) been our goal since we started, October 27, 2008,” Voss said.
“Now we’re on the cusp of that, but we haven’t achieved it. To do that, this becomes a critically big game for us (against North Melbourne on Saturday night). You’ve got to make sure that you put your home wins away.”
Voss rates the Kangaroos highly despite a string of narrow defeats, and expects them to be keen to atone for their draw with Richmond on Sunday.
“Off a draw you feel completely empty,” Voss said.
“Their motivation levels, I would have thought, will be quite high to try and get that win on the board that they’ve probably been working towards for the best part of a month.”
