"It just got to that point to where we've got to get him productive in some role," Sveum said of Marmol. "He was fine with it and understood, and hopefully we can get him going to where we give him another chance and get him going and get back in that role."
Thursday's poor outing was just the most recent in a string of them for Marmol, who has struggled with his command. The right-hander leads Chicago's pitching staff -- including starters -- with 12 walks in 8 2/3 innings. In comparison, starters Matt Garza and Jeff Samardzija have each issued 10 walks in 33 2/3 and 31 2/3 innings, respectively.
"Who knows whether it's mechanical, mental," Sveum said. "His [bullpen sessions], his side sessions are good. The game speeds up a little bit and gets pumping, [and] everything just breaks down a little bit. That's why, as much as anything, we have to make him a productive pitcher in whatever role it is for us."
Sveum said he was still unsure what that role would be. He said he told Marmol to be ready to pitch in any situation.
As far as choosing a definitive closer between Russell and Dolis, Sveum said, for now, he'll stick to whichever ninth-inning matchups work best.
Dolis, a rookie, has allowed only two earned runs in his past 8 1/3 innings as the club's primary setup man. Russell, now in his third season, has yet to allow a run in nine appearances spanning 7 2/3 innings.
"[We hope] somebody steps up and takes control of any situation or role that we give somebody, but it's not the easiest thing to do in the world, either, to get those last three outs in games," Sveum said. "We're just going to play it by ear, and whatever matchups are coming up in that ninth inning, that'll be who I'll use."
If the Cubs do, indeed, save Russell for the ninth inning, that leaves another hole in their bullpen: left-handed specialist. Russell is the only lefty in the 'pen, and Sveum acknowledged Friday he can no longer use Russell as freely in the sixth or seventh innings as he has, but said he's willing to if it's the right situation.
"There might be a situation where a team might have two, three, three out of four lefties coming up in the seventh inning," Sveum said. "We'll use Russell in that inning and we'll wing the rest of it or something."