The decisive moment on Saturday night began with a slashed single to left by Tigers infielder Harold Castro, and it ended with JaCoby Jones diving head-first across home plate and Cubs closer Craig Kimbrel making the walk of defeat off the field.

That was the final snapshot of Chicago's ugly 9-8, 10-inning loss at Comerica Park, but it had its roots much earlier in the evening. The initial domino in the North Siders' fourth defeat in five games was an abbreviated start by Trevor Williams.

• Box score

"It was a really good scratch, tooth-and-nail fight from our offense," Williams said. "To see what they did, to hang in the game the whole time was really impressive, especially as deflating as it is to see a starter only last two innings."

Here are three takeaways from Saturday's loss in the Motor City:

1. Williams' short outing
Over the next few days, Williams will team with pitching coach Tommy Hottovy and the Cubs' pitching group to dissect what happened in Detroit. First, however, Williams plans on having a follow-up discussion with manager David Ross.

Williams did not expect to be lifted after two innings and 42 pitches.

"I tried to talk him out of it," Williams said. "We talked. I'm sure we'll have conversations again [Sunday] and kind of see just where we're at in terms of what he saw, what I saw. But the team really did a great job today picking me up."

After the lineup spotted Williams a 2-0 lead in the first inning, the right-hander allowed three runs in the home half of the frame. That outburst included a leadoff double by Robbie Grossman, followed by a walk to Jeimer Candelario, setting up the rough start.

"He just didn't look real sharp," Ross said. "He was having to work really hard. Even when he was getting ahead, not being able to put guys away. Falling behind to some guys. Just the at-bats from the other team, there weren't too many of those guys that seemed fooled by much."

The two-inning showing gave Williams 11 runs allowed on 15 hits in 8 2/3 innings in his last three turns combined. He has 10 strikeouts against eight walks in that small sample. The righty tried to focus on the silver linings in the wake of his latest effort.

"I thought they hit executed pitches," he said. "But other than that, it's just looking at the positives. I'm looking forward to these next four days of work."

2. Duffy's big day
After crossing home plate in the fifth inning, Cubs third baseman Matt Duffy allowed himself to smile. After all, it had been 595 days since he last launched a home run in the Majors.

"We were talking about it in the dugout," Duffy said. "There's two ways to react after you hit a homer. You can either act cool like, 'I've been there,' or you can just say, 'Screw it,’ and just be ecstatic.

"It's like, 'I don't do that very often, so I'm just going to smile and enjoy it. I don't care what anyone says.'"

Duffy delivered a trio of go-ahead hits in an effort to help the Cubs overcome the pitching's tough day. All three of his hits came with two strikes.

Duffy's RBI double off José Ureña in the third gave Chicago a 4-3 lead. His three-run homer off Alex Lange in the fifth put the Cubs up, 7-6. In the 10th, Duffy lined Michael Fulmer's pitch to right to put the Tigers behind, 8-7.

"He's been a big spark plug for us," Ross said. "He uses all fields. It's a quality AB every time. He doesn't seem to get off balance too much. He knows the strike zone. We trust in his contact."

3. Thompson keeps impressing
Keegan Thompson came up through the Cubs' farm system as a starting pitcher. Right now, he is not only navigating the Majors for the first time but learning about life in the bullpen and leverage situations on the fly.

And that is fine by the rookie.

"I've always been a starter," Thompson said. "But I'll tell you what, whatever keeps me up here, I'll do whatever they ask me to do."

Thompson was brilliant in a two-inning appearance on Saturday, striking out five of the seven batters he faced. That helped bridge the gap to Kimbrel in the 10th -- an ideal way for Ross to line things up, even if it did not work in the end.

What stood out this time from Thompson was a sudden jump in whiff rate. Coming into the game, the righty had generated just four swinging strikes out of 126 pitches thrown with Chicago. Against Detroit, he had eight whiffs out of 13 swings (four via the cutter and three with the curve).

Overall, Thompson has allowed just one unearned run in 10 1/3 innings since joining the Cubs' pitching staff.

"Listen, we want outs," Ross said. "I don't care if they swing and miss or they hit it at somebody. That doesn't matter to me. ... For a young man to come in and do as good as he has, there's been no complaints here. I think we all know what he's capable of."