McAdam: Injuries to Betts, Nunez, ineffectiveness by Pomeranz couldn't happen at a worse time

And to think, things had been going so well.

The Red Sox returned to Fenway Park Monday, fresh off their most successful road trip of the season, winners of six straight and eight of their last nine.

They started the final homestand of the season with a magic number of three to lock up their second straight AL East title. With seven games remaining, clinching was a mere formality.

It still is. Monday night’s 6-4 loss to Toronto merely postponed that eventuality for a day. The Red Sox still lead by four with just six games remaining.

But it’s what happened inside the loss that should concern the Red Sox:

• Drew Pomeranz was hammered for five runs in two-plus innings, his shortest outing of the season. Equally troubling was the diminished velocity on his fastball, part of a trend over his last few starts.

• Eduardo Nunez, who returned to the lineup following a 13-game absence, exited again after just three innings, having aggravated his ailing right knee when his spike got caught at home plate as he took a swing.

• Mookie Betts, who had been on a tear, left the game in the eighth inning with a sore left wrist that will be further examined Tuesday.

This is not the time of year when you want these kinds of developments. This week was supposed to be about dotting i’s and crossing t’s and getting ready for the postseason. Take care of business, get some rest for a few regulars and pop the Champagne.

Now, there’s reason for at least some concern. The team’s No. 2 starter, approaching a career high in innings, didn’t look sharp. Pomeranz's four-seamer, which he’s typically thrown at 92 mph, has been 88-90 mph the last two times out.

“Not as sharp overall,’’ acknowledged John Farrell. “I think it’s where we are on the calendar. I can’t say it’s anything physical. But we recognize that he’s got to locate a little more consistently and use his mix a little more thoroughly.’’

Pomeranz downplayed the drop-off and insisted he was suffering from a loss of arm strength in the final week of a long season.

“I feel fine,’’ he said. “I was throwing some two-seamers a little slower and trying to get some swings on it. I was trying to work on location away, and I kept missing. I feel pretty good. Obviously, a short outing tonight, but I feel good. My velocity’s dipped a few times in my last few outings, but then I get right back up when I need it. Tonight, I didn’t get a chance to settle in and work some of those higher velocity (fastballs) in there.’’

Perhaps what Pomeranz says is true, and this is more about late-season experimentation than anything more troubling. But the lack of life on the fastball can set off an alarm with Pomeranz set as the Red Sox’ presumed No. 2 starter.

Then there’s Betts, who has been swinging the last few weeks better than he has all season, with 13 extra-base hits in his last 16 games, with 21 RBI and a .662 slugging percentage in that span.

But he was seen flexing his wrist repeatedly for the training staff in the dugout and left the game for a pinch-hitter in the eighth.

Betts said the origin of the wrist problem was “a couple of days ago and it’s been painful on some swings. But that’s just part of the season. … I think it will be fine.’’

He described the sensation as “a sharp pain…I can’t really move my hand. I don’t really know what’s going on. We’ll find out (Tuesday).’’

That hardly sounds encouraging. If there’s one person the Sox can’t afford to not have at full strength, it’s Betts, inarguably their best overall player. When he’s swinging the bat as he has in recent weeks, he changes their lineup.

If he’s limited, so is the Red Sox’ lineup at a time when they can least afford to be.

Finally, there’s Nunez, whose excitement over returning to the lineup Monday night lasted all of a couple at-bats.

Farrell admitted they don’t know when he’ll be ready to play again and the Sox may have to give up on him playing the field in the postseason, limiting their lineup options.

“We don’t feel like there was added damage,’’ said Farrell. “He just aggravated it. I don’t have a real clear indication of when he’d be next available.’’

That was one more bit of bad news on a night when the final score was the least of their worries.