Trades can be completed after this Deadline, but doing so becomes more difficult. That's why the bulk of each season's trade activity comes before the start of August.
The absence of any deals consummated by the Cardinals thus far should not be confused with a dearth of discussion. General manager John Mozeliak has made it clear that he will explore all avenues to put the defending World Series champions in position to return to the playoffs. The Cards currently sit 7 1/2 games behind the first-place Reds and 3 1/2 games out of the second NL Wild Card spot.
Prospects aren't off the table for the right return. But the necessity of improving the club by making external additions also doesn't seem to be as immediate as that of other clubs with more glaring deficiencies to address.
To understand the Cardinals' trade-or-not-to-trade dilemma, perhaps it's unnecessary to look much beyond their run differential this season.
The club has scored 498 runs (the most in the NL) and allowed only 404. That run differential of plus-94 is the best in the Majors, heading into Monday's action. And yet the Cards' .529 winning percentage is only 12th best in baseball.
That discrepancy, of course, is explained by the fact that St. Louis is 16-29 in games determined by two or fewer runs but boasts a 19-9 record in games decided by at least five. And that run differential hits on the Cardinals' most pointed question: Which area can they tweak to significantly improve the club?
Not only have the Redbirds scored more runs than any NL team this season, but their team batting average (.275) and on-base percentage (.344) are also the league's best. The offensive unit is entirely healthy, too, which leaves the Cardinals with no obvious area to address.
That's not to say that the club hasn't considered boosting its bench and depth, but it has left the Cards unwilling to forfeit too much future talent for what would likely be only a slight position-player upgrade.
Needs on the pitching end have fluctuated, particularly over the past four weeks.
A month ago, it seemed pretty certain that the Cardinals would actively seek to bolster their rotation and the bullpen. At the time, Lance Lynn was enduring his first struggles of the season. It was becoming evident that right-hander Chris Carpenter likely wouldn't be able to contribute in 2012. And Jaime Garcia's timetable was still in flux.
But over the past few weeks, much has settled, even with the news that Carpenter is indeed out all year. Garcia is likely only about two weeks away from rejoining the rotation, and Lynn doesn't appear to be hampered by fatigue. The rest of the rotation has held strong, too, and will enter Tuesday with a 2.72 July ERA. The group has had just one start of fewer than six innings all month.
One month of terrific results from the rotation hasn't stopped St. Louis from exploring possible starting-pitching acquisitions. But again, there's no desperation to add -- especially if the price tag is top Minor League talent.
The bullpen has always been the area that seemed an obvious spot for the Cardinals to improve. The unit's ERA of 4.10 is higher than the NL average, and finding a reliable bridge from the starters to Mitchell Boggs and Jason Motte has been among manager Mike Matheny's toughest tasks in his first season at the helm.
But something happened in July to give the Cards less reason to panic. This month, the 'pen has limited teams to a .204 batting average and has posted a 2.14 ERA. Barret Browning and Trevor Rosenthal have offered St. Louis new young faces. And Brian Fuentes was lured in after being released from Oakland. The veteran lefty has made two scoreless appearances so far.
Still, there is concern about the long-term sustainability of this recent success, which means bullpen help remains on the club's wish list. The crop of available relievers, though, isn't overwhelmingly strong. And again, the Cardinals always have to balance short-term gain with long-term sacrifice.
So with fewer than 24 hours remaining before the non-waiver Deadline, perhaps it is not surprising that the Cards have been among the inactive. Discussions between Mozeliak and other GMs will continue through Tuesday afternoon. Whether that will bring a trade to fruition, though, is not so certain.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.