For the first time in recent years, St. Louis Cardinal fans are having upset stomachs. For Cubs fans prior to 2015, this feeling was natural. It was getting close to the deadline, the Cubs were sitting below .500, and it was that time to evaluate which players on the team could be flipped for prospects.

For St. Louis, this in unfamiliar territory. Can a fan honestly remember a time when the Cardinals were sellers at the trade deadline? The Cardinals have just one losing season since 2000, and that was in 2007 when the team finished 78-84. Even during that season, the Cardinals made no rash trades for prospects.

Their only acquisition that season was for the pitcher, Mike Maroth.

The Cardinals are a mess right now with a 31-36 record. They are 4.5 games out of first place, but odds are saying that the Cardinals are not going to come out of this funk. The question remains. Could the Cardinals be sellers the last week of July?

The answer is yes

Even if it is not the "Cardinal Way," the Cardinals could absolutely be sellers this year. The Cardinals have been masters at developing their own talent, but it doesn't get rid of the golden rule that if you aren't going anywhere, then you should get something back for what you might lose.

The Cardinals have only two free agents this upcoming season in Lance Lynn and Zach Duke.

The Cardinals also have a bounce back year in Trevor Rosenthal, who isn't a free agent until 2019. The pitching market is down this year, and if the Cardinals are not in contention, then it might be time to be a seller come July 31.

The case to trade Lynn

Lynn is a 30-year-old pitcher that is having a fantastic season after missing all of the 2016 season.

Lynn commands a 2.69 earned run average to go with a 5-3 record. Teams like the Colorado Rockies and Houston Astros will be looking to add another starter to make a deep postseason run. The Astros have the prospects to make a trade. If the Astros can't get a top starter like Tampa Bay's, Chris Archer, they could look at a guy like Lynn.

Adam Wainwright is getting up there in years at the age of 35 and is a free agent in 2019. It might be time to start stockpiling for the future of the rotation that already has studs like Carlos Martinez and Michael Wacha.

Trade Rosenthal now while his value is up

Rosenthal is just two years away from that 2015 season where he saved 48 games with a 2.10 ERA. Rosenthal is having a better campaign this year than his 4.46 ERA days in 2016. Rosenthal has a 3.65 ERA with three saves in what is more of a middle relief role this season. He is just 27 years old, and a playoff contender could get star struck from the past to make a deal to help bolster their bullpen. Look at a team like the Diamondbacks who could be interested in the right hander.