Portsmouth perils prove a point as Sunderland struggle in key area: six things we learned from Walsall

But the Scot will take plenty of lessons from the FA Cup exit ahead of a hectic festive fixture period - which could have a big bearing on the Black Cats' season.

So what key lessons should Sunderland take from their narrow defeat to the Saddlers?

We take a look at six of the key things we learned from the visit of Walsall:

The corners need to start counting

We've said it before and we'll say it again - Sunderland need to start making their attacking set pieces count.

The Black Cats had eight corners on Tuesday evening but failed to threaten from any of them.

LIVE: Transfer, injury and contract latest from the Stadium of LightSome were played short, others put straight into the mixer - but none caused any sort of worry to the Walsall backline.

That is a key area that needs to improve, as corners could be an extra weapon in Sunderland's arsenal as the season progresses,

Duncan Watmore can be a major outlet

Having now featured a couple of times under Ross, it's clear to see how the attacker will fit into the Scot's system.

Watmore's pace and directness allow him to stretch the opposition, providing space for the Black Cats' midfielders to surge forward.

RATINGS: How 'fatigued' Sunderland stars fared against WalsallWhile it was only evident in spells against Walsall, it seems Ross has a good understanding of how the 24-year-old can add to his style of play.

Jack Ross' principles remain - no matter what

Ross is often calmness personified on the touchline, and his team reflect that - even when chasing a game.

Whether rightly or wrongly, Sunderland resisted the temptation to go long when searching for a leveller.

READ: No excuses for Ross as Sunderland exit FA CupPlenty would argue it has been a long time since the Wearsiders had a set style of football, and it's refreshing to see Ross isn't willing to abandon that at the first sign of trouble.

Aiden McGeady's spark was a real miss

Side-lined with a knock, the absence of McGeady was felt against the Saddlers.

The Black Cats enjoyed plenty of possession but failed to trouble Liam Roberts in the Walsall goal - fashioning just one shot on target.

MORE: Ross hopeful that key duo will return on Saturday afternoonMcGeady's creative influence and attacking spark could have helped to unlock a stubborn visiting defence, and his return will be welcomed on Saturday.

Are Walsall becoming THAT team?

Every team has that one bogey side - so are Walsall becoming Sunderland's nemesis this season?

The pair have become familiar foes in recent weeks but the Black Cats are yet to register a victory over their midland rivals.

READ: Sunderland fans react to FA Cup exitSo while the duo won't face off again until March 16, ending the bogey run may be on the minds of Ross' side when they lock horns once again in three months' time.

Portsmouth's perils show why the league must remain a priority

A key positive for Sunderland last night was Portsmouth's defeat to play-off chasing Charlton - which stopped Kenny Jackett's side from opening up a big lead at the top of League One.

And their slip-up proves why the Black Cats must continue to treat the league as their priority.

While a Wembley date in the Checkatrade Trophy may prove appealing, Sunderland need to ensure their focus remains on the third tier so they can capitalise on their rivals dropping points in what is proving to be a fiercely competitive promotion battle.