It wasn't entirely surprising that tight end/co-captain Rob Gronkowski wasn't on the practice field Thursday. Leaving the Jets game in the first quarter with a back injury, cancelling a community appearance earlier this week, and being held out of yesterday's session were all indications that he was unlikely to suit up this week against the L.A. Rams.

What no one outside the football offices at Gillette Stadium could have expected, though, was the news this afternoon that Gronk will undergo surgery tomorrow – coincidentally, in Los Angeles – for a herniated (ruptured) disc. With a reported timetable of eight weeks before Gronkowski can resume football activities, some of today's other absences from practice might make some sense when examined more closely.

The Patriots currently have just two other tight ends on the active roster: Martellus Bennett, who's dealing with ankle and shoulder injuries himself and didn't really do much of anything at Wednesday's practice, and Matt Lengel, a young player who's only been active in a game once in his NFL career (Week 11 at San Francisco).

Entering today, the club had just one tight end on its practice squad, but that player, Kennard Backman, was not seen at the start of today's session and is presumed to have been released for the second time this season.

With Gronkowski's situation, how could the team afford to part with any tight ends at this point? Perhaps because there's a need for depth at other positions as well.

For example, rookie defensive lineman Woodrow Hamilton was not on the field Thursday, nor was he listed on the injury report. It's possible that he, too, has been released to open up a roster spot for a tight end (presumably one more experienced than  Backman). If Hamilton has been released and isn't picked up by another club, it's entirely possible that he could then be re-signed to the Patriots' practice squad because New England needs to maintain its depth at defensive tackle.

Retaining a player like Hamilton is imperative for the Patriots considering that they have just three other d-tackles (Alan Branch, Malcom Brown, and rookie Vincent Valentine) and Branch's future availability remains uncertain, as he is in the midst of an appeal of a four-game NFL suspension.

Of course, it's also possible that Hamilton's and Backman's absences are for other reasons and entirely unrelated to the Gronkowski situation, but given the lack of information available, we're doing our best to connect dots and provide you with plausible scenarios.

Two other absences to report this Thursday, one a surprise, the other not so much. Defensive end Trey Flowers, who wasn't on the injury report, wasn't on the field at the start of practice. Neither was safety Jordan Richards, who is dealing with a knee injury sustained this past Sunday against the Jets. He's missed two days of practice this week.

Brady, Edelman return

On a positive note, quarterback/co-captain Tom Brady suited up today after taking Wednesday off to nurse his ailing right knee. He took two days off last week to rest the injury, so, it appears he's making progress in his recovery.

Meanwhile, one of his favorite targets, wide receiver Julian Edelman, also was back on the field after a Wednesday absence. He's been listed for a while now on the injury report with his lingering left foot issue, but media reports indicate that Edelman wasn't present yesterday because he was in Los Angeles (there's that city again) to be with Swedish model Ella Rose and witness the birth of their first child, a daughter, according to those same reports.

"We're really happy for him," fellow wideout Chris Hogan remarked Thursday. "He's going to do great [as a father]."

Edelman was in the locker room briefly during the media interview portion of the day, just before practice, but he did not speak with reporters.  

Elsewhere at practice, the aforementioned Bennett looked to be a bit more active than yesterday, when he did little more than ride a stationary bike while reporters and cameras were present. Safety Nate Ebner also appeared to do more in the drill period after stretching. He was officially listed as not having participated in yesterday's practice due to a concussion, although he was on the field and suited up while the media was in attendance.