The Chicago Cubs edged the San Diego Padres last night thanks to a stellar performance from their bullpen. However, that didn't stop manager Joe Maddon from saying the club still needs to upgrade in that department.

Is it crazy to say Chicago may look to explore a trade for Jonathan Papelbon?

Maybe, but it's not awfully crazy. The fact that Papelbon is on the trading block and is still one of the top closers in the MLB provides our first clue. His incumbent team, the Philadelphia Phillies, want prospect(s) in return for his services and the Cubs have plenty of those. And most importantly, Cubs' president of baseball operations Theo Epstein knows Papelbon very well from their days in Boston. This should get the rumors rolling.

In the offseason, Jim Salisbury of CSN Philly noted Papelbon can't block trades to 12 MLB clubs, one of which is the Cubs.

"[General manager Jed] Hoyer should be asking about Philadelphia's Jonathan Papelbon to give the Cubs an established closer, a move that would allow Hector Rondon to move into a more flexible relief role," writes Dan O'Dowd of MLB.com.

Chicago has payroll flexibility, and considering Papelbon's $13 million vesting option is looking like it's going to kick in for 2016, Hoyer and Epstein have some leverage in the talks regarding who they might give up for the closer.

Rumors suggest they've already gotten the ball rolling.

"One of the areas the front office is expected to address before the trade deadline is the bullpen. And according to Bruce Levine [of 670thescore.com], the Cubs are interested in RHP Jonathan Papelbon and have had internal discussions about the veteran closer," according to Chicago Cubs Online.

Chicago's bullpen ranks 22nd in the league in ERA (4.20) thanks to issues in recent weeks and Maddon thinks some changes need to be made. The team already began that transformation after designating Phil Coke for assignment and moving Travis Wood from the rotation into a relief role earlier this week.

"The big part of our problem is we have not made big pitches out of the bullpen when we've needed to," Maddon told Jesse Rogers of ESPNChicago.com. "I think that's the No. 1 item we have to clean up.

"We need to firm up the bullpen. Saying that, I like the arms on the people down there."

Justin Grimm has stepped in nicely thus far. The team acquired Yoervis Medina from the Mariners earlier in the week in the trade that sent catcher Welington Castillo to Seattle, but he'll be in Triple-A for a little bit. James Russell has been solid, but his WHIP (1.32) as a reliever could use improvement.

The duo of Hector Rondon as closer and Pedro Strop as setup man might not be enough to ensure the Cubs success in late-inning situations. Strop has been knocked around as of late (8.64 ERA in last 8 1/3 innings). Rodon has been reliable, but his lone good season came in 2014 and it's unknown if he'll be able to sustain success in the closer role. He's nine-for-11 in save opportunities this season and owns a 3.00 ERA and 1.278 WHIP, which is solid, but he has allowed multiple baserunners in three of his past seven appearances. The concerns may be mounting in Chicago.

On the other hand, Papelbon owns a 1.50 ERA and 0.889 WHIP with 11 saves and 23 strikeouts in 18 innings of work. He has yet to blow a save and has finished 17 of his 18 games.

The Cubs likely aren't to jump ship on Rondon has their closer just yet, but it should be known Papelbon could be a realistic option if the club is seriously considering upgrading the bullpen.