How Tottenham manager Mauricio Pochettino can rotate his squad
Mauricio Pochettino shuffled his pack for Thursday's Europa League Round of 32 first leg at Fiorentina, making six changes from the side that won 2-1 at Manchester City.
It was an indication the Tottenham manager is ready to prioritise Spurs' Premier League title push and a further sign will come on Sunday when Pochettino rotates again for the FA Cup fifth-round match against Crystal Palace.
Spurs have already played 37 matches this season and could play up to 26 more if they progress to both cup finals, which could leave their boss with a difficult juggling act to ensure his small squad avoids fatigue, as was the case last season.
ESPN FC looked at the numbers to determine how the Argentine could manage his squad.
The last time Tottenham used the same full-backs in consecutive matches was in December when, seven days apart, Kyle Walker and Ben Davies faced Southampton and Norwich. In the 12 games since, Pochettino has rotated on one or both sides.
"The full-backs that play for Tottenham are explosive players," said Walker last month. "They cover nearly the most ground on the pitch, getting up and back, so it's vital that we come to the games fresh, rather than playing two games in a week."
Pochettino's full-backs also boast different styles, which allow him to select with the opposition in mind. For example, while Walker averages just 2 crosses per league match, Kieran Trippier manages 5.8.
The first-choice full-back pairing is Walker and Danny Rose, who have started 23 and 20 matches respectively in all competitions, but neither is likely to exceed 35, even if Spurs go all the way in both cups.
At centre-back the situation is more complex, particularly with Jan Vertonghen sidelined until late March.
While it might be true that these players need less rest than their teammates -- Vertonghen and Toby Alderweireld have made a combined 71 starts, compared to the 43 of Walker and Rose -- Alderweireld and Kevin Wimmer ran a combined 20.86 kilometres at Man City, which was just marginally less than Walker and Rose, who covered 21.74 km.
Before Vertonghen was injured, the two Belgians had played every minute of Tottenham's 23 league matches. Wimmer has deputised admirably and Pochettino can rotate the left-footers once Vertonghen returns.
But the only cover for Alderweireld, who has played 2880 minutes for Spurs this season, is Eric Dier. He has started all but two of Tottenham's matches this season and is in need of a break as much as his teammate.
Pochettino likes 18-year-old Cameron Carter-Vickers but the U.S. U21 international is not ready for the first team. As such, the manager's only option is to continue to alternate the rest games of Alderweireld and Dier, as he did in Florence on Thursday when the former started and the latter was on the bench.
It follows that Dier is likely to partner Wimmer against Palace, just as he did against Leicester and Colchester in previous FA Cup rounds.
When Vertonghen returns, it will be interesting to see if Pochettino pairs him with Wimmer. The two left-footers have never been on the pitch at the same time.
Mousa Dembele has made 21 starts in all competitions, while Tom Carroll has 13 and Ryan Mason just 10.
Dembele, one of Spurs' best performers this season, is comfortably first-choice but Pochettino trusts the English duo, who know each other from the academy and combined effectively in the first half in Florence, which means the Belgian should be afforded plenty of time off in the run-in.
As noted, it is Dier whose workload must be most closely monitored. Thursday's game was just the second match he has missed this season -- he was suspended for the October draw with Liverpool -- and, when he is on the pitch, he typically covers more ground than any other player except Christian Eriksen, averaging over 11 km per match.
Nabil Bentaleb is the best fit to cover for Dier but, having excelled last season, the Algerian has struggled in 2015-16 and was not named in the squad for each of the last three games. If that trend continues on Sunday, it seems unlikely he will feature prominently again this season.
Eriksen (34 starts), Dele Alli (29) and Erik Lamela (29) have featured regularly but Son Heung-Min (17) and Nacer Chadli (16) are fresh, while 18-year-old Joshua Onomah is trusted by Pochettino and Clinton Njie has been injured since December.
Son has only covered 97.3 km so far this season -- compared to Eriksen's 253.1 km and Alli's 242.9 km -- and, while this is partly a result of contrasting playing styles, it also suggests the South Korean should increase in influence as the campaign progresses.
Eriksen, in particular, will need a rest. Last season the Dane covered more ground -- 395 km -- than any other player in the league and it cost him. He finished 2014-15 with 10 goals but only one came after February.
Meanwhile, Alli is just 19 and shows no signs of tiring but he has completed more sprints -- 1,480 -- than all but three players in the league and Pochettino will be wary of burning him out.
Harry Kane has covered more ground -- 277.7 km -- than any other forward in the league and so there is reason to think he will need a break. In his remarkable breakthrough campaign, just two of the 31 goals he scored in all competitions came in the final two months of the season.
Pochettino has admitted that Kane is his "only proper" striker but the Argentine also has faith in Chadli to play as an auxiliary No. 9 and, in three starts there, the Belgian has scored four goals. Beyond that, Son is also an option.
The manager demands his striker presses relentlessly from the front, a role that might become increasingly tough for Kane to fulfil as the season progresses. When fit, Njie was often asked to be the "runner" in the final stages of matches and the energetic 23-year-old could resume this role when he comes back.
Pochettino is often accused of over-reliance on Kane but, while the England international will need some rest, provided he remains fit the manager's biggest headache will be finding time off for Dier and Alderweireld.
The pair are shoo-ins to start Tottenham's 12 remaining league matches but their boss must carefully manage them in the Europa League and FA Cup, particularly if he is unwilling to recall Bentaleb or use Wimmer and Vertonghen as a pair.
Eriksen and Alli will also need to be subtly rotated in the months ahead, which is why the versatility of Chadli, Son and Njie could prove invaluable. All three -- and possibly Lamela -- can expect to play minutes on the wing and up front.
Dan is ESPN FC's Tottenham correspondent. Follow him on Twitter: @Dan_KP.