After Sunday, there will just three weeks left in the Major League Baseball regular season. The Baltimore Orioles have been in contention all season and continue to be, but the AL playoff race is so tight that they could be the AL East champ, the first wild card, the second wild card or miss the playoffs entirely.

Part of what will help determine that for the O's is how well their weakness performs. That is, of course, the starting rotation. Entering Sunday, the Orioles ranked 25th in the majors with a 4.84 rotation ERA. The only teams worse are very bad (Angels, Reds, A's, Diamondbacks, Twins).

Things are looking up, though, and Sunday was very encouraging.

Chris Tillman returned from the disabled list after dealing with a sholder injury and went out and threw well in Detroit in a wild-card battle. He would allow only one run on four hits in six innings, helping lead the Orioles to a big 3-1 victory. The win moves Tillman to 16-5 with a 3.68 ERA on the season and the Orioles two games ahead of the Tigers for the second wild card (the Yankees are also two back now after their loss).

Welcome back, Chris Tillman. USATSI

Seeing something encouraging for the rotation moving forward has become a bit common this month. Orioles starters are 6-1 with a 3.21 ERA. Their lowest ERA in any other month was 4.55 and that was all the way back in April. It started before the calendar turned from August, though:

Now that Tillman is back, he is probably considered the ace of the staff and he looked the part on Sunday. Who is the number two? Kevin Gausman. Many non-Orioles fans might not have noticed, but he's been very good for a while now. In his 11 starts since the All-Star break, Gausman is 6-4 with a 2.89 ERA and 73 strikeouts in 65 1/3 innings. In his last four starts, the ERA is a sparkling 1.08. The 26-year-old former first rounder is clearly putting it all together and, in fact, I wouldn't argue if someone wanted to say he is the ace.

Speaking of former first rounders, Dylan Bundy has been a mixed bag. He was crushed last time out against the hapless Rays, but he's had several very good outings, such as his Sept. 2 win over the Yankees (5 2/3 scoreless innings). He also had a five-start stretch earlier with a 1.84 ERA. Given the inconsistency, he should probably be slotted as the number four starter when thinking about a possible playoff rotation.

And that's where offseason signee Yovani Gallardo comes in.

Gallardo has been awful for most of this season. He has a good track record, though, and had a 3.42 ERA in 33 starts for the Rangers last season. Has he turned a corner? In his last two starts, Gallardo has allowed only four earned runs in 11 innings (3.27 ERA). The three home runs are still problematic and it's a small sample, but it can offer some semblance of encouragement.

If Gallardo continues to build on those two starts and looks more like the 2015 version of Gallardo, they might really have something there. Tillman and Gausman will be reliable and Bundy will continue to flash his immense upside on occasion.

It should be noted that Ubaldo Jimenez has a 2.83 ERA in four starts since his return to the rotation. I still don't trust him, but it's possible he ends up taking that spot instead of Gallardo. We've seen Jimenez excel in stretches before. If nothing else, it gives manager Buck Showalter several options as the O's fight for the playoffs down the stretch.

So is a Tillman, Gausman, Gallardo/Jimenez, Bundy playoff rotation going to scare people? Nope. Given that the Orioles possess one of baseball's most powerful offenses and a stellar back-end of the bullpen, it could well be good enough for a deep playoff run. They have to get there first and they'll only go as far as their weakness allows them. For now, there's enough reason for optimism and one of those specific reasons was on display Sunday with Tillman's return.